Make Gr clear take a rect for a partial-clear

Review URL: http://codereview.appspot.com/4442093/



git-svn-id: http://skia.googlecode.com/svn/trunk@1203 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/gpu/src/GrContext.cpp b/gpu/src/GrContext.cpp
index 0584e4b..d3904e0 100644
--- a/gpu/src/GrContext.cpp
+++ b/gpu/src/GrContext.cpp
@@ -391,11 +391,9 @@
 
 ////////////////////////////////////////////////////////////////////////////////
 
-void GrContext::clear(GrColor color) {
-    // gpu flush call is immediate, must flush. 
-    // (could in theory skip draws to current render target.)
+void GrContext::clear(const GrIRect* rect, const GrColor color) {
     this->flush();
-    fGpu->clear(color);
+    fGpu->clear(rect, color);
 }
 
 void GrContext::drawPaint(const GrPaint& paint) {
@@ -462,7 +460,7 @@
     // clip gets applied in second pass
     target->disableState(GrDrawTarget::kClip_StateBit);
 
-    target->clear(0x0);
+    target->clear(NULL, 0x0);
     return true;
 }