When running DM, write test failures to json.

Add skiatest::Failure to keep track of data about a test failure.

Reporter::reportFailed and ::onReportFailed now take Failure as a
parameter. This allows the implementation to treat the failure as it
wishes. Provide a helper to format the failure the same as prior to
the change.

Update the macros for calling reportFailed (REPORTER_ASSERT etc) to
create a Failure object.

Convert a direct call to reportFailed to the macro ERRORF.

Write Failures to Json.
Sample output when running dm on the dummy test crrev.com/705723004:
{
   "test_results" : {
      "failures" : [
         {
            "condition" : "0 > 3",
            "file_name" : "../../tests/DummyTest.cpp",
            "line_no" : 10,
            "message" : ""
         },
         {
            "condition" : "false",
            "file_name" : "../../tests/DummyTest.cpp",
            "line_no" : 4,
            "message" : ""
         },
         {
            "condition" : "1 == 3",
            "file_name" : "../../tests/DummyTest.cpp",
            "line_no" : 5,
            "message" : "I can too count!"
         },
         {
            "condition" : "",
            "file_name" : "../../tests/DummyTest.cpp",
            "line_no" : 6,
            "message" : "seven is 7"
         },
         {
            "condition" : "1 == 3",
            "file_name" : "../../tests/DummyTest.cpp",
            "line_no" : 14,
            "message" : "I can too count!"
         }
      ]
   }
}

Report all of the failures from one test.
Previously, if one test had multiple failures, only one was reportered.
e.g:

Failures:
  test Dummy: ../../tests/DummyTest.cpp:6   seven is 7
  test Dummy2: ../../tests/DummyTest.cpp:10 0 > 3
  test Dummy3: ../../tests/DummyTest.cpp:14 I can too count!: 1 == 3
3 failures.

Now, we get all the messages:

Failures:
  test Dummy: ../../tests/DummyTest.cpp:4   false
        ../../tests/DummyTest.cpp:5 I can too count!: 1 == 3
        ../../tests/DummyTest.cpp:6 seven is 7
  test Dummy2: ../../tests/DummyTest.cpp:10 0 > 3
  test Dummy3: ../../tests/DummyTest.cpp:14 I can too count!: 1 == 3
3 failures.

(Note that we still state "3 failures" because 3 DM::Tasks failed.)

BUG=skia:3082
BUG=skia:2454

Review URL: https://codereview.chromium.org/694703005
diff --git a/dm/DMJsonWriter.cpp b/dm/DMJsonWriter.cpp
index f862647..a2de38b 100644
--- a/dm/DMJsonWriter.cpp
+++ b/dm/DMJsonWriter.cpp
@@ -24,6 +24,14 @@
     gBitmapResults.push_back(result);
 }
 
+SkTArray<skiatest::Failure> gFailures;
+SK_DECLARE_STATIC_MUTEX(gFailureLock);
+
+void JsonWriter::AddTestFailure(const skiatest::Failure& failure) {
+    SkAutoMutexAcquire lock(gFailureLock);
+    gFailures.push_back(failure);
+}
+
 void JsonWriter::DumpJson() {
     if (FLAGS_writePath.isEmpty()) {
         return;
@@ -52,6 +60,19 @@
         }
     }
 
+    {
+        SkAutoMutexAcquire lock(gFailureLock);
+        for (int i = 0; i < gFailures.count(); i++) {
+            Json::Value result;
+            result["file_name"]     = gFailures[i].fileName;
+            result["line_no"]       = gFailures[i].lineNo;
+            result["condition"]     = gFailures[i].condition;
+            result["message"]       = gFailures[i].message.c_str();
+
+            root["test_results"]["failures"].append(result);
+        }
+    }
+
     SkString path = SkOSPath::Join(FLAGS_writePath[0], "dm.json");
     SkFILEWStream stream(path.c_str());
     stream.writeText(Json::StyledWriter().write(root).c_str());
diff --git a/dm/DMJsonWriter.h b/dm/DMJsonWriter.h
index c358fdd..66ce530 100644
--- a/dm/DMJsonWriter.h
+++ b/dm/DMJsonWriter.h
@@ -9,6 +9,7 @@
 #define DMJsonWriter_DEFINED
 
 #include "SkString.h"
+#include "Test.h"
 
 namespace DM {
 
@@ -35,6 +36,11 @@
     static void AddBitmapResult(const BitmapResult&);
 
     /**
+     *  Add a Failure from a Test.
+     */
+    static void AddTestFailure(const skiatest::Failure&);
+
+    /**
      *  Write all collected results to the file FLAGS_writePath[0]/dm.json.
      */
     static void DumpJson();
diff --git a/dm/DMTestTask.h b/dm/DMTestTask.h
index ceb0e12..9a47b35 100644
--- a/dm/DMTestTask.h
+++ b/dm/DMTestTask.h
@@ -2,6 +2,7 @@
 #define DMTestTask_DEFINED
 
 #include "DMReporter.h"
+#include "DMJsonWriter.h"
 #include "DMTask.h"
 #include "DMTaskRunner.h"
 #include "SkString.h"
@@ -21,8 +22,16 @@
   virtual bool allowExtendedTest() const SK_OVERRIDE;
   virtual bool verbose()           const SK_OVERRIDE;
 
-  virtual void onReportFailed(const SkString& desc) SK_OVERRIDE {
-      fFailure = desc;
+  virtual void onReportFailed(const skiatest::Failure& failure) SK_OVERRIDE {
+      JsonWriter::AddTestFailure(failure);
+
+      SkString newFailure;
+      failure.getFailureString(&newFailure);
+      // TODO: Better to store an array of failures?
+      if (!fFailure.isEmpty()) {
+          fFailure.append("\n\t\t");
+      }
+      fFailure.append(newFailure);
   }
 
   SkString fFailure;
diff --git a/tests/GrTRecorderTest.cpp b/tests/GrTRecorderTest.cpp
index a5aedf6..83bc445 100644
--- a/tests/GrTRecorderTest.cpp
+++ b/tests/GrTRecorderTest.cpp
@@ -214,7 +214,7 @@
                 break;
 
             default:
-                reporter->reportFailed(SkString("Invalid class type"));
+                ERRORF(reporter, "Invalid class type");
                 break;
         }
     }
diff --git a/tests/Test.cpp b/tests/Test.cpp
index c458f89..acbc332 100644
--- a/tests/Test.cpp
+++ b/tests/Test.cpp
@@ -31,8 +31,8 @@
     this->onStart(test);
 }
 
-void Reporter::reportFailed(const SkString& desc) {
-    this->onReportFailed(desc);
+void Reporter::reportFailed(const skiatest::Failure& failure) {
+    this->onReportFailed(failure);
 }
 
 void Reporter::endTest(Test* test) {
@@ -63,11 +63,11 @@
     explicit LocalReporter(Reporter* reporterToMimic) : fReporter(reporterToMimic) {}
 
     int numFailures() const { return fFailures.count(); }
-    const SkString& failure(int i) const { return fFailures[i]; }
+    const skiatest::Failure& failure(int i) const { return fFailures[i]; }
 
 protected:
-    virtual void onReportFailed(const SkString& desc) SK_OVERRIDE {
-        fFailures.push_back(desc);
+    virtual void onReportFailed(const Failure& failure) SK_OVERRIDE {
+        fFailures.push_back(failure);
     }
 
     // Proxy down to fReporter.  We assume these calls are threadsafe.
@@ -85,7 +85,7 @@
 
 private:
     Reporter* fReporter;  // Unowned.
-    SkTArray<SkString> fFailures;
+    SkTArray<skiatest::Failure> fFailures;
 };
 
 void Test::run() {
diff --git a/tests/Test.h b/tests/Test.h
index 6c85b32..90cd259 100644
--- a/tests/Test.h
+++ b/tests/Test.h
@@ -20,6 +20,40 @@
 
     class Test;
 
+    /**
+     *  Information about a single failure from a Test.
+     *
+     *  Not intended to be created/modified directly. To create one, use one of
+     *
+     *  REPORTER_ASSERT
+     *  REPORTER_ASSERT_MESSAGE
+     *  ERRORF
+     *
+     *  described in more detail further down in this file.
+     */
+    struct Failure {
+        const char* fileName;
+        int lineNo;
+        const char* condition;
+        SkString message;
+
+        // Helper to combine the failure info into one string.
+        void getFailureString(SkString* result) const {
+            if (!result) {
+                return;
+            }
+            result->printf("%s:%d\t", fileName, lineNo);
+            if (!message.isEmpty()) {
+                result->append(message);
+                if (strlen(condition) > 0) {
+                    result->append(": ");
+                }
+            }
+            result->append(condition);
+        }
+    };
+
+
     class Reporter : public SkRefCnt {
     public:
         SK_DECLARE_INST_COUNT(Reporter)
@@ -28,7 +62,7 @@
         int countTests() const { return fTestCount; }
 
         void startTest(Test*);
-        void reportFailed(const SkString& desc);
+        void reportFailed(const Failure&);
         void endTest(Test*);
 
         virtual bool allowExtendedTest() const { return false; }
@@ -37,7 +71,7 @@
 
     protected:
         virtual void onStart(Test*) {}
-        virtual void onReportFailed(const SkString& desc) {}
+        virtual void onReportFailed(const Failure&) {}
         virtual void onEnd(Test*) {}
 
     private:
@@ -110,31 +144,31 @@
     }
 */
 
-#define REPORTER_ASSERT(r, cond)                                 \
-    do {                                                         \
-        if (!(cond)) {                                           \
-            SkString desc;                                       \
-            desc.printf("%s:%d\t%s", __FILE__, __LINE__, #cond); \
-            r->reportFailed(desc);                               \
-        }                                                        \
+#define REPORTER_ASSERT(r, cond)                                        \
+    do {                                                                \
+        if (!(cond)) {                                                  \
+            skiatest::Failure failure = { __FILE__, __LINE__,           \
+                                          #cond, SkString() };          \
+            r->reportFailed(failure);                                   \
+        }                                                               \
     } while(0)
 
-#define REPORTER_ASSERT_MESSAGE(r, cond, message)            \
-    do {                                                     \
-        if (!(cond)) {                                       \
-            SkString desc;                                   \
-            desc.printf("%s:%d\t%s: %s", __FILE__, __LINE__, \
-                        message, #cond);                     \
-            r->reportFailed(desc);                           \
-        }                                                    \
+#define REPORTER_ASSERT_MESSAGE(r, cond, message)                       \
+    do {                                                                \
+        if (!(cond)) {                                                  \
+            skiatest::Failure failure = { __FILE__, __LINE__,           \
+                                          #cond, SkString(message) };   \
+            r->reportFailed(failure);                                   \
+        }                                                               \
     } while(0)
 
-#define ERRORF(reporter, ...)                       \
-    do {                                            \
-        SkString desc;                              \
-        desc.printf("%s:%d\t", __FILE__, __LINE__); \
-        desc.appendf(__VA_ARGS__) ;                 \
-        (reporter)->reportFailed(desc);             \
+#define ERRORF(r, ...)                                                  \
+    do {                                                                \
+        SkString desc;                                                  \
+        desc.appendf(__VA_ARGS__) ;                                     \
+        skiatest::Failure failure = { __FILE__, __LINE__,               \
+                                      "", SkString(desc) };             \
+        r->reportFailed(failure);                                       \
     } while(0)
 
 #define DEF_TEST(name, reporter)                                        \
diff --git a/tests/skia_test.cpp b/tests/skia_test.cpp
index 172328e..3d76c3a 100644
--- a/tests/skia_test.cpp
+++ b/tests/skia_test.cpp
@@ -58,7 +58,9 @@
     virtual bool verbose()           const SK_OVERRIDE { return FLAGS_veryVerbose; }
 
 protected:
-    virtual void onReportFailed(const SkString& desc) SK_OVERRIDE {
+    virtual void onReportFailed(const skiatest::Failure& failure) SK_OVERRIDE {
+        SkString desc;
+        failure.getFailureString(&desc);
         SkDebugf("\nFAILED: %s", desc.c_str());
     }