Update from chromium a8e7c94b1b79a0948d05a1fcfff53391d22ce37a

cc/output/software_renderer.cc

 // Copyright 2012 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/output/software_renderer.h"
 
 #include "base/debug/trace_event.h"
 #include "cc/base/math_util.h"
 #include "cc/output/compositor_frame.h"
 #include "cc/output/compositor_frame_ack.h"
@@ skipping 221 matching lines @@
   QuadRectTransform(&quad_rect_matrix, quad->quadTransform(), quad->rect);
   gfx::Transform contents_device_transform =
       frame->window_matrix * frame->projection_matrix * quad_rect_matrix;
   contents_device_transform.FlattenTo2d();
   SkMatrix sk_device_matrix;
   gfx::TransformToFlattenedSkMatrix(contents_device_transform,
                                     &sk_device_matrix);
   current_canvas_->setMatrix(sk_device_matrix);
 
   current_paint_.reset();
-  if (!IsScaleAndIntegerTranslate(sk_device_matrix)) {
+  if (settings_->force_antialiasing ||
+      !IsScaleAndIntegerTranslate(sk_device_matrix)) {
     // TODO(danakj): Until we can enable AA only on exterior edges of the
     // layer, disable AA if any interior edges are present. crbug.com/248175
     bool all_four_edges_are_exterior = quad->IsTopEdge() &&
                                        quad->IsLeftEdge() &&
                                        quad->IsBottomEdge() &&
                                        quad->IsRightEdge();
-    if (settings_->allow_antialiasing && all_four_edges_are_exterior)
+    if (settings_->allow_antialiasing &&
+        (settings_->force_antialiasing || all_four_edges_are_exterior))
       current_paint_.setAntiAlias(true);
     current_paint_.setFilterLevel(SkPaint::kLow_FilterLevel);
   }
 
   if (quad->ShouldDrawWithBlending() ||
       quad->shared_quad_state->blend_mode != SkXfermode::kSrcOver_Mode) {
     current_paint_.setAlpha(quad->opacity() * 255);
     current_paint_.setXfermodeMode(quad->shared_quad_state->blend_mode);
   } else {
     current_paint_.setXfermodeMode(SkXfermode::kSrc_Mode);
@@ skipping 338 matching lines @@
 }
 
 void SoftwareRenderer::DidChangeVisibility() {
   if (visible())
     EnsureBackbuffer();
   else
     DiscardBackbuffer();
 }
 
 }  // namespace cc