Disable GPU rasterization on low-end devices.

content/renderer/gpu/render_widget_compositor.cc

 // Copyright (c) 2013 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 "content/renderer/gpu/render_widget_compositor.h"
 
 #include <limits>
 #include <string>
 
 #include "base/command_line.h"
@@ skipping 312 matching lines @@
     }
   }
 
   settings.strict_layer_property_change_checking =
       cmd->HasSwitch(cc::switches::kStrictLayerPropertyChangeChecking);
 
 #if defined(OS_ANDROID)
   SynchronousCompositorFactory* synchronous_compositor_factory =
       SynchronousCompositorFactory::GetInstance();
 
+  // We can't use GPU rasterization on low-end devices, because the Ganesh
+  // cache would consume too much memory.
+  if (base::SysInfo::IsLowEndDevice())
+    settings.gpu_rasterization_enabled = false;
   settings.using_synchronous_renderer_compositor =
       synchronous_compositor_factory;
   settings.record_full_layer = widget->DoesRecordFullLayer();
   settings.report_overscroll_only_for_scrollable_axes =
       !synchronous_compositor_factory;
   settings.max_partial_texture_updates = 0;
   if (synchronous_compositor_factory) {
     // Android WebView uses system scrollbars, so make ours invisible.
     settings.scrollbar_animator = cc::LayerTreeSettings::NoAnimator;
     settings.solid_color_scrollbar_color = SK_ColorTRANSPARENT;
   } else {
     settings.scrollbar_animator = cc::LayerTreeSettings::LinearFade;
     settings.scrollbar_fade_delay_ms = 300;
     settings.scrollbar_fade_resize_delay_ms = 2000;
     settings.scrollbar_fade_duration_ms = 300;
     settings.solid_color_scrollbar_color = SkColorSetARGB(128, 128, 128, 128);
   }
   settings.renderer_settings.highp_threshold_min = 2048;
   // Android WebView handles root layer flings itself.
   settings.ignore_root_layer_flings =
       synchronous_compositor_factory;
   // Memory policy on Android WebView does not depend on whether device is
   // low end, so always use default policy.
-  bool is_low_end_device =
+  bool use_low_memory_policy =
       base::SysInfo::IsLowEndDevice() && !synchronous_compositor_factory;
   // RGBA_4444 textures are only enabled for low end devices
   // and are disabled for Android WebView as it doesn't support the format.
-  settings.renderer_settings.use_rgba_4444_textures = is_low_end_device;
-  if (is_low_end_device) {
+  settings.renderer_settings.use_rgba_4444_textures = use_low_memory_policy;
+  if (use_low_memory_policy) {
     // On low-end we want to be very carefull about killing other
     // apps. So initially we use 50% more memory to avoid flickering
     // or raster-on-demand.
     settings.max_memory_for_prepaint_percentage = 67;
   } else {
     // On other devices we have increased memory excessively to avoid
     // raster-on-demand already, so now we reserve 50% _only_ to avoid
     // raster-on-demand, and use 50% of the memory otherwise.
     settings.max_memory_for_prepaint_percentage = 50;
   }
@@ skipping 519 matching lines @@
   widget_->OnSwapBuffersAborted();
 }
 
 void RenderWidgetCompositor::RateLimitSharedMainThreadContext() {
   cc::ContextProvider* provider =
       RenderThreadImpl::current()->SharedMainThreadContextProvider().get();
   provider->ContextGL()->RateLimitOffscreenContextCHROMIUM();
 }
 
 }  // namespace content