Allow using a larger-than-necessary texture as cached render pass backing

cc/render_pass_draw_quad.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/render_pass_draw_quad.h"
 
 namespace cc {
 
 RenderPassDrawQuad::RenderPassDrawQuad()
     : render_pass_id(RenderPass::Id(-1, -1)),
       is_replica(false),
-      mask_resource_id(-1),
-      mask_tex_coord_scale_x(0),
-      mask_tex_coord_scale_y(0),
-      mask_tex_coord_offset_x(0),
-      mask_tex_coord_offset_y(0) {
+      mask_resource_id(-1) {
 }
 
 scoped_ptr<RenderPassDrawQuad> RenderPassDrawQuad::Create() {
     return make_scoped_ptr(new RenderPassDrawQuad);
 }
 
 scoped_ptr<RenderPassDrawQuad> RenderPassDrawQuad::Copy(
     const SharedQuadState* copied_shared_quad_state,
     RenderPass::Id copied_render_pass_id) const {
   scoped_ptr<RenderPassDrawQuad> copy_quad(new RenderPassDrawQuad(*MaterialCast(this)));
   copy_quad->shared_quad_state = copied_shared_quad_state;
   copy_quad->render_pass_id = copied_render_pass_id;
   return copy_quad.Pass();
 }
 
 void RenderPassDrawQuad::SetNew(const SharedQuadState* shared_quad_state,
                                 gfx::Rect rect,
                                 RenderPass::Id render_pass_id,
                                 bool is_replica,
                                 ResourceProvider::ResourceId mask_resource_id,
                                 gfx::Rect contents_changed_since_last_frame,
-                                float mask_tex_coord_scale_x,
-                                float mask_tex_coord_scale_y,
-                                float mask_tex_coord_offset_x,
-                                float mask_tex_coord_offset_y) {
+                                gfx::RectF mask_uv_rect) {
   DCHECK(render_pass_id.layer_id > 0);
   DCHECK(render_pass_id.index >= 0);
 
   gfx::Rect opaque_rect;
   gfx::Rect visible_rect = rect;
   bool needs_blending = false;
   DrawQuad::SetAll(shared_quad_state, DrawQuad::RENDER_PASS, rect, opaque_rect,
                    visible_rect, needs_blending);
   this->render_pass_id = render_pass_id;
   this->is_replica = is_replica;
   this->mask_resource_id = mask_resource_id;
   this->contents_changed_since_last_frame = contents_changed_since_last_frame;
-  this->mask_tex_coord_scale_x = mask_tex_coord_scale_x;
-  this->mask_tex_coord_scale_y = mask_tex_coord_scale_y;
-  this->mask_tex_coord_offset_x = mask_tex_coord_offset_x;
-  this->mask_tex_coord_offset_y = mask_tex_coord_offset_y;
+  this->mask_uv_rect = mask_uv_rect;
 }
 
 void RenderPassDrawQuad::SetAll(const SharedQuadState* shared_quad_state,
                                 gfx::Rect rect,
                                 gfx::Rect opaque_rect,
                                 gfx::Rect visible_rect,
                                 bool needs_blending,
                                 RenderPass::Id render_pass_id,
                                 bool is_replica,
                                 ResourceProvider::ResourceId mask_resource_id,
                                 gfx::Rect contents_changed_since_last_frame,
-                                float mask_tex_coord_scale_x,
-                                float mask_tex_coord_scale_y,
-                                float mask_tex_coord_offset_x,
-                                float mask_tex_coord_offset_y) {
+                                gfx::RectF mask_uv_rect) {
   DCHECK(render_pass_id.layer_id > 0);
   DCHECK(render_pass_id.index >= 0);
 
   DrawQuad::SetAll(shared_quad_state, DrawQuad::RENDER_PASS, rect, opaque_rect,
                    visible_rect, needs_blending);
   this->render_pass_id = render_pass_id;
   this->is_replica = is_replica;
   this->mask_resource_id = mask_resource_id;
   this->contents_changed_since_last_frame = contents_changed_since_last_frame;
-  this->mask_tex_coord_scale_x = mask_tex_coord_scale_x;
-  this->mask_tex_coord_scale_y = mask_tex_coord_scale_y;
-  this->mask_tex_coord_offset_x = mask_tex_coord_offset_x;
-  this->mask_tex_coord_offset_y = mask_tex_coord_offset_y;
+  this->mask_uv_rect = mask_uv_rect;
 }
 
 const RenderPassDrawQuad* RenderPassDrawQuad::MaterialCast(
     const DrawQuad* quad) {
   DCHECK(quad->material == DrawQuad::RENDER_PASS);
   return static_cast<const RenderPassDrawQuad*>(quad);
 }
 
 }  // namespace cc