Revert of Sketch splitting SkPicture into an interface and SkBigPicture.

tests/GpuLayerCacheTest.cpp

Index: tests/GpuLayerCacheTest.cpp
diff --git a/tests/GpuLayerCacheTest.cpp b/tests/GpuLayerCacheTest.cpp
index efb1ec1c203e44570d66c37a025fca3d7ff873f6..6b3084b641cbe99b84a7156d238fe8fbb803f3ed 100644
--- a/tests/GpuLayerCacheTest.cpp
+++ b/tests/GpuLayerCacheTest.cpp
@@ -111,10 +111,7 @@
         }
 
         SkPictureRecorder recorder;
-        SkCanvas* c = recorder.beginRecording(1, 1);
-            // Draw something, anything, to prevent an empty-picture optimization,
-            // which is a singleton and never purged.
-            c->drawRect(SkRect::MakeWH(1,1), SkPaint());
+        recorder.beginRecording(1, 1);
         SkAutoTUnref<const SkPicture> picture(recorder.endRecording());
 
         GrLayerCache cache(context);