Move some work from backend onClear to base class clear

src/gpu/GrGpu.cpp

Index: src/gpu/GrGpu.cpp
diff --git a/src/gpu/GrGpu.cpp b/src/gpu/GrGpu.cpp
index bb020f5b503d7ac7c7207fcc663e37e00542bab2..267edf1eb0473c67c05c3c51644624fd381e490f 100644
--- a/src/gpu/GrGpu.cpp
+++ b/src/gpu/GrGpu.cpp
@@ -218,11 +218,10 @@ GrIndexBuffer* GrGpu::createIndexBuffer(size_t size, bool dynamic) {
 
 void GrGpu::clear(const SkIRect* rect,
                   GrColor color,
-                  bool canIgnoreRect,
                   GrRenderTarget* renderTarget) {

[bsalomon, 2015/08/06 16:04:14]

Shouldn't this now just require a rect param (const & instead of const *)? Also
could assert that rect is contained in the rt rect.

[egdaniel, 2015/08/06 17:02:53]

Done.

     SkASSERT(renderTarget);
     this->handleDirtyContext();
-    this->onClear(renderTarget, rect, color, canIgnoreRect);
+    this->onClear(renderTarget, rect, color);
 }
 
 void GrGpu::clearStencilClip(const SkIRect& rect,