Minor GrContext/GrInOrderDrawBuffer cleanup

https://codereview.chromium.org/18341007/



git-svn-id: http://skia.googlecode.com/svn/trunk@9898 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/GrInOrderDrawBuffer.h b/src/gpu/GrInOrderDrawBuffer.h
index 6090235..0871cc5 100644
--- a/src/gpu/GrInOrderDrawBuffer.h
+++ b/src/gpu/GrInOrderDrawBuffer.h
@@ -63,12 +63,8 @@
      * is destructive). This buffer must not have an active reserved vertex or index source. Any
      * reserved geometry on the target will be finalized because it's geometry source will be pushed
      * before flushing and popped afterwards.
-     *
-     * @return false if the playback trivially drew nothing because nothing was recorded.
      */
-    bool flush();
-
-    bool isFlushing() const { return fFlushing; }
+    void flush();
 
     // overrides from GrDrawTarget
     virtual bool geometryHints(int* vertexCount,