Add option to draw wireframe batch bounds

include/gpu/GrContextOptions.h

Index: include/gpu/GrContextOptions.h
diff --git a/include/gpu/GrContextOptions.h b/include/gpu/GrContextOptions.h
index 52173eb7a0a081055e3c8217c5b160fa95837e23..2874b52be7a64c9c929c0edd18d91474f1165833 100644
--- a/include/gpu/GrContextOptions.h
+++ b/include/gpu/GrContextOptions.h
@@ -21,6 +21,7 @@ struct GrContextOptions {
         , fUseDrawInsteadOfPartialRenderTargetWrite(false)
         , fImmediateMode(false)
         , fClipBatchToBounds(false)
+        , fDrawBatchBounds(false)
         , fUseShaderSwizzling(false) {}
 
     // EXPERIMENTAL
@@ -57,6 +58,11 @@ struct GrContextOptions {
         verify that the clip bounds are conservative. */
     bool fClipBatchToBounds;
 
+    /** For debugging purposes draw a wireframe device bounds rect for each GrBatch. The wire
+        frame rect is draw before the GrBatch in order to visualize batches that draw outside
+        of their dev bounds. */
+    bool fDrawBatchBounds;
+
     /** Force us to do all swizzling manually in the shader and don't rely on extensions to do
         swizzling. */
     bool fUseShaderSwizzling;