cc: Remove incorrect dcheck for masks.

cc/layers/render_surface_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/render_surface_impl.h"
 
 #include <algorithm>
 
 #include "base/logging.h"
 #include "base/stringprintf.h"
@@ skipping 232 matching lines @@
     if (mask_layer &&
         (!mask_layer->DrawsContent() || mask_layer->bounds().IsEmpty()))
       mask_layer = NULL;
   }
 
   gfx::RectF mask_uv_rect(0.f, 0.f, 1.f, 1.f);
   if (mask_layer) {
     gfx::Vector2dF owning_layer_draw_scale =
         MathUtil::ComputeTransform2dScaleComponents(
             owning_layer_->draw_transform(), 1.f);
-    gfx::SizeF unclipped_surface_size = gfx::ScaleSize(
+    gfx::SizeF unclipped_masked_layer_size = gfx::ScaleSize(
         owning_layer_->content_bounds(),
         owning_layer_draw_scale.x(),
         owning_layer_draw_scale.y());
-    // This assumes that the owning layer clips its subtree when a mask is
-    // present.
-    DCHECK(gfx::RectF(unclipped_surface_size).Contains(content_rect_));
 
-    float uv_scale_x = content_rect_.width() / unclipped_surface_size.width();
-    float uv_scale_y = content_rect_.height() / unclipped_surface_size.height();
+    float uv_scale_x =
+        content_rect_.width() / unclipped_masked_layer_size.width();
+    float uv_scale_y =
+        content_rect_.height() / unclipped_masked_layer_size.height();
 
     mask_uv_rect = gfx::RectF(
         uv_scale_x * content_rect_.x() / content_rect_.width(),
         uv_scale_y * content_rect_.y() / content_rect_.height(),
         uv_scale_x,
         uv_scale_y);
   }
 
   ResourceProvider::ResourceId mask_resource_id =
       mask_layer ? mask_layer->ContentsResourceId() : 0;
   gfx::Rect contents_changed_since_last_frame =
       ContentsChanged() ? content_rect_ : gfx::Rect();
 
   scoped_ptr<RenderPassDrawQuad> quad = RenderPassDrawQuad::Create();
   quad->SetNew(shared_quad_state,
                content_rect_,
                render_pass_id,
                for_replica,
                mask_resource_id,
                contents_changed_since_last_frame,
                mask_uv_rect,
                owning_layer_->filters(),
                owning_layer_->filter(),
                owning_layer_->background_filters());
   quad_sink->Append(quad.PassAs<DrawQuad>(), append_quads_data);
 }
 
 }  // namespace cc