Skip drawing unsupported layers in forced software mode

cc/layers/tiled_layer_impl.cc

 // Copyright 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/layers/tiled_layer_impl.h"
 
 #include "base/basictypes.h"
 #include "base/stringprintf.h"
 #include "cc/base/math_util.h"
 #include "cc/debug/debug_colors.h"
@@ skipping 137 matching lines @@
     DrawableTile* tile = static_cast<DrawableTile*>(iter->second);
 
     tiled_layer->PushTileProperties(i,
                                     j,
                                     tile->resource_id(),
                                     tile->opaque_rect(),
                                     tile->contents_swizzled());
   }
 }
 
+bool TiledLayerImpl::WillDraw(DrawMode draw_mode,
+                              ResourceProvider* resource_provider) {
+  if (!tiler_ || tiler_->has_empty_bounds() ||
+      visible_content_rect().IsEmpty() ||
+      draw_mode == DRAW_MODE_RESOURCELESS_SOFTWARE)
+    return false;
+  return LayerImpl::WillDraw(draw_mode, resource_provider);
+}
+
 void TiledLayerImpl::AppendQuads(QuadSink* quad_sink,
                                  AppendQuadsData* append_quads_data) {
+  DCHECK(tiler_);
+  DCHECK(!tiler_->has_empty_bounds());
+  DCHECK(!visible_content_rect().IsEmpty());
+
   gfx::Rect content_rect = visible_content_rect();
-
-  if (!tiler_ || tiler_->has_empty_bounds() || content_rect.IsEmpty())
-    return;
-
   SharedQuadState* shared_quad_state =
       quad_sink->UseSharedQuadState(CreateSharedQuadState());
   AppendDebugBorderQuad(quad_sink, shared_quad_state, append_quads_data);
 
   int left, top, right, bottom;
   tiler_->ContentRectToTileIndices(content_rect, &left, &top, &right, &bottom);
 
   if (ShowDebugBorders()) {
     for (int j = top; j <= bottom; ++j) {
       for (int i = left; i <= right; ++i) {
@@ skipping 134 matching lines @@
   CHECK(tiler_);
   tiler_->reset();
   s_safe_to_delete_drawable_tile = false;
 }
 
 const char* TiledLayerImpl::LayerTypeAsString() const {
   return "cc::TiledLayerImpl";
 }
 
 }  // namespace cc