Restrict query bounds for reduce clip to dev bounds

src/gpu/batches/GrBatch.h

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrBatch_DEFINED
 #define GrBatch_DEFINED
 
@@ skipping 13 matching lines @@
  * subclasses complete freedom to decide how / what they can batch.
  *
  * Batches are created when GrContext processes a draw call. Batches of the same  subclass may be
  * merged using combineIfPossible. When two batches merge, one takes on the union of the data
  * and the other is left empty. The merged batch becomes responsible for drawing the data from both
  * the original batches.
  *
  * If there are any possible optimizations which might require knowing more about the full state of
  * the draw, ie whether or not the GrBatch is allowed to tweak alpha for coverage, then this
  * information will be communicated to the GrBatch prior to geometry generation.
+ *
+ * The bounds of the batch must contain all the pixels that would be modified *irrespective* of the
+ * clip. The bounds are used in determining which clip elements must be applied and thus the bounds
+ * cannot in turn depend upon the clip.
  */
 #define GR_BATCH_SPEW 0
 #if GR_BATCH_SPEW
     #define GrBATCH_INFO(...) SkDebugf(__VA_ARGS__)
     #define GrBATCH_SPEW(code) code
 #else
     #define GrBATCH_SPEW(code)
     #define GrBATCH_INFO(...)
 #endif
 
@@ skipping 104 matching lines @@
 #if GR_BATCH_SPEW
     static uint32_t GenBatchID() { return GenID(&gCurrBatchUniqueID); }
     const uint32_t                      fUniqueID;
     static int32_t                      gCurrBatchUniqueID;
 #endif
     static int32_t                      gCurrBatchClassID;
     typedef GrNonAtomicRef INHERITED;
 };
 
 #endif