Revert "Disable coverage counting by default"

This reverts commit 576b2a5596bc8dda294a069e3fdc6b8b8e48ffcf.

Reason for revert: DDL and MSRTC unhappy

Original change's description:
> Disable coverage counting by default
> 
> Bug: skia:
> Change-Id: Iacb4cb3e409c6abdd25319ec0884ef673fb04cec
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/201101
> Reviewed-by: Brian Salomon <bsalomon@google.com>
> Commit-Queue: Chris Dalton <csmartdalton@google.com>

TBR=djsollen@google.com,bsalomon@google.com,csmartdalton@google.com

Change-Id: Iabdb3116d97c7470044b962ff78cffd47ccee744
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: skia:
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/201933
Reviewed-by: Chris Dalton <csmartdalton@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>
diff --git a/tools/flags/SkCommonFlags.cpp b/tools/flags/SkCommonFlags.cpp
index dfacdbe..be569f8 100644
--- a/tools/flags/SkCommonFlags.cpp
+++ b/tools/flags/SkCommonFlags.cpp
@@ -161,7 +161,7 @@
 
 DEFINE_bool(noGS, false, "Disables support for geometry shaders.");
 
-DEFINE_string(pr, "",
+DEFINE_string(pr, "all",
               "Set of enabled gpu path renderers. Defined as a list of: "
               "[~]none [~]dashline [~]nvpr [~]ccpr [~]aahairline [~]aaconvex [~]aalinearizing "
               "[~]small [~]tess] [~]all");
diff --git a/tools/flags/SkCommonFlagsGpu.h b/tools/flags/SkCommonFlagsGpu.h
index 65871e3..d546078 100644
--- a/tools/flags/SkCommonFlagsGpu.h
+++ b/tools/flags/SkCommonFlagsGpu.h
@@ -46,9 +46,9 @@
 
 inline GpuPathRenderers CollectGpuPathRenderersFromFlags() {
     if (FLAGS_pr.isEmpty()) {
-        return GpuPathRenderers::kDefault;
+        return GpuPathRenderers::kAll;
     }
-    GpuPathRenderers gpuPathRenderers = ('~' == FLAGS_pr[0][0])
+    GpuPathRenderers gpuPathRenderers = '~' == FLAGS_pr[0][0]
             ? GpuPathRenderers::kAll : GpuPathRenderers::kNone;
     for (int i = 0; i < FLAGS_pr.count(); ++i) {
         const char* name = FLAGS_pr[i];