Add new GM to directly exercise perspective bitmap drawing

src/gpu/GrDrawContext.cpp

Index: src/gpu/GrDrawContext.cpp
diff --git a/src/gpu/GrDrawContext.cpp b/src/gpu/GrDrawContext.cpp
index b11518f018fe89d86444785b053291c6ebc1b7e3..e03075e41f5f412f392233855535910bf2565697 100644
--- a/src/gpu/GrDrawContext.cpp
+++ b/src/gpu/GrDrawContext.cpp
@@ -273,11 +273,11 @@ void GrDrawContext::drawRect(GrRenderTarget* rt,
 
     // The fill path can handle rotation but not skew
     // The stroke path needs the rect to remain axis aligned (no rotation or skew)
-    // None of our draw rect calls can handle perspective yet
-    SkASSERT(!viewMatrix.hasPerspective());
+    // None of our AA draw rect calls can handle perspective yet
     bool canApplyAA = width >=0 ? viewMatrix.rectStaysRect() : viewMatrix.preservesRightAngles();
 
     if (needAA && canApplyAA) {
+        SkASSERT(!viewMatrix.hasPerspective());
         SkRect devBoundRect;
         viewMatrix.mapRect(&devBoundRect, rect);
         SkAutoTUnref<GrDrawBatch> batch;