Add support to dump font cache texture for debug purposes

R=robertphillips@google.com, bsalomon@google.com

Author: jvanverth@google.com

Review URL: https://codereview.chromium.org/25736002

git-svn-id: http://skia.googlecode.com/svn/trunk@11579 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/GrTextStrike.cpp b/src/gpu/GrTextStrike.cpp
index e399c91..7cab335 100644
--- a/src/gpu/GrTextStrike.cpp
+++ b/src/gpu/GrTextStrike.cpp
@@ -10,6 +10,7 @@
 #include "GrRectanizer.h"
 #include "GrTextStrike.h"
 #include "GrTextStrike_impl.h"
+#include "SkString.h"
 
 SK_DEFINE_INST_COUNT(GrFontScaler)
 SK_DEFINE_INST_COUNT(GrKey)
@@ -170,6 +171,23 @@
 }
 #endif
 
+#ifdef SK_DEVELOPER
+void GrFontCache::dump() const {
+    static int gDumpCount = 0;
+    for (int i = 0; i < kMaskFormatCount; ++i) {
+        if (NULL != fAtlasMgr[i]) {
+            GrTexture* texture = fAtlasMgr[i]->getTexture();
+            if (NULL != texture) {
+                SkString filename;
+                filename.printf("fontcache_%d%d.png", gDumpCount, i);
+                texture->savePixels(filename.c_str());
+            }
+        }
+    }
+    ++gDumpCount;
+}
+#endif
+
 ///////////////////////////////////////////////////////////////////////////////
 
 #ifdef SK_DEBUG