Add a command-line switch --enable-per-tile-painting and make it consistent by changing --enable-accelerated-drawing to --enable-accelerated-painting.

With this switch, webkit compositor will paint tiles separately.

BUG=none
TEST=no behavior change in existing browser tests and ui tests

Review URL: http://codereview.chromium.org/8771056

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@114694 0039d316-1c4b-4281-b951-d872f2087c98

8 files changed, 50 insertions, 24 deletions

diff --git a/chrome/app/generated_resources.grd b/chrome/app/generated_resources.grd
index b4e9a27..1f3d5b1 100644
--- a/chrome/app/generated_resources.grd
+++ b/chrome/app/generated_resources.grd
@@ -4730,11 +4730,11 @@ Keep your key file in a safe place. You will need it to create new versions of y
       <message name="IDS_FLAGS_COMPOSITED_LAYER_BORDERS_DESCRIPTION" desc="Description of the 'Composited layer borders' lab.">
         Renders a border around composited Render Layers to help debug and study layer compositing.
       </message>
-      <message name="IDS_FLAGS_ACCELERATED_DRAWING_NAME" desc="Title for the flag to enable accelerated drawing">
-        GPU Accelerated Drawing
+      <message name="IDS_FLAGS_ACCELERATED_PAINTING_NAME" desc="Title for the flag to enable accelerated painting">
+        GPU Accelerated Painting
       </message>
-      <message name="IDS_FLAGS_ACCELERATED_DRAWING_DESCRIPTION" desc="Description for the flag to enable accelerated drawing">
-        Enable GPU accelerated drawing of page contents when compositing is enabled.
+      <message name="IDS_FLAGS_ACCELERATED_PAINTING_DESCRIPTION" desc="Description for the flag to enable accelerated painting">
+        Enable GPU accelerated painting of page contents when compositing is enabled.
       </message>
       <message name="IDS_FLAGS_SHOW_FPS_COUNTER" desc="Name of the 'Show FPS counter' lab.">
         FPS counter
@@ -5004,6 +5004,12 @@ Keep your key file in a safe place. You will need it to create new versions of y
       <message name="IDS_FLAGS_ENABLE_GAMEPAD_DESCRIPTION" desc="Description for the flag to enable gamepad support.">
         This API allows web applications to access data from gamepad devices connected to the system.
       </message>
+      <message name="IDS_FLAGS_PER_TILE_PAINTING_NAME" desc="Title for the flag to enable per-tile painting">
+        Per-tile Painting
+      </message>
+      <message name="IDS_FLAGS_PER_TILE_PAINTING_DESCRIPTION" desc="Description for the flag to enable per-tile painting">
+        Enable per-tile painting of page contents when compositing is enabled.
+      </message>
 
       <!-- Crashes -->
       <message name="IDS_CRASHES_TITLE" desc="Title for the chrome://crashes page.">
diff --git a/chrome/browser/about_flags.cc b/chrome/browser/about_flags.cc
index c983e2d..7386c5c 100644
--- a/chrome/browser/about_flags.cc
+++ b/chrome/browser/about_flags.cc
@@ -154,15 +154,15 @@ const Experiment kExperiments[] = {
     SINGLE_VALUE_TYPE(switches::kShowCompositedLayerBorders)
   },
   {
-    "accelerated-drawing",
-    IDS_FLAGS_ACCELERATED_DRAWING_NAME,
-    IDS_FLAGS_ACCELERATED_DRAWING_DESCRIPTION,
+    "accelerated-painting",
+    IDS_FLAGS_ACCELERATED_PAINTING_NAME,
+    IDS_FLAGS_ACCELERATED_PAINTING_DESCRIPTION,
 #if defined(USE_SKIA)
     kOsAll,
 #else
     0,
 #endif
-    SINGLE_VALUE_TYPE(switches::kEnableAcceleratedDrawing)
+    SINGLE_VALUE_TYPE(switches::kEnableAcceleratedPainting)
   },
   {
     "show-fps-counter",
@@ -457,6 +457,17 @@ const Experiment kExperiments[] = {
     SINGLE_VALUE_TYPE(switches::kAuraLaptopMode)
   },
 #endif
+  {
+    "per-tile-painting",
+    IDS_FLAGS_PER_TILE_PAINTING_NAME,
+    IDS_FLAGS_PER_TILE_PAINTING_DESCRIPTION,
+#if defined(USE_SKIA)
+    kOsAll,
+#else
+    0,
+#endif
+    SINGLE_VALUE_TYPE(switches::kEnablePerTilePainting)
+  },
 };
 
 const Experiment* experiments = kExperiments;
diff --git a/chrome/browser/tab_contents/render_view_host_delegate_helper.cc b/chrome/browser/tab_contents/render_view_host_delegate_helper.cc
index a8ad499..499af98 100644
--- a/chrome/browser/tab_contents/render_view_host_delegate_helper.cc
+++ b/chrome/browser/tab_contents/render_view_host_delegate_helper.cc
@@ -458,9 +458,9 @@ WebPreferences RenderViewHostDelegateHelper::GetWebkitPrefs(
     web_prefs.accelerated_2d_canvas_enabled =
         GpuProcessHost::gpu_enabled() &&
         !command_line.HasSwitch(switches::kDisableAccelerated2dCanvas);
-    web_prefs.accelerated_drawing_enabled =
+    web_prefs.accelerated_painting_enabled =
         GpuProcessHost::gpu_enabled() &&
-        command_line.HasSwitch(switches::kEnableAcceleratedDrawing);
+        command_line.HasSwitch(switches::kEnableAcceleratedPainting);
     web_prefs.accelerated_filters_enabled =
         GpuProcessHost::gpu_enabled() &&
         command_line.HasSwitch(switches::kEnableAcceleratedFilters);
@@ -506,9 +506,10 @@ WebPreferences RenderViewHostDelegateHelper::GetWebkitPrefs(
 
     web_prefs.visual_word_movement_enabled =
         command_line.HasSwitch(switches::kEnableVisualWordMovement);
-
     web_prefs.unified_textchecker_enabled =
         command_line.HasSwitch(switches::kExperimentalSpellcheckerFeatures);
+    web_prefs.per_tile_painting_enabled =
+        command_line.HasSwitch(switches::kEnablePerTilePainting);
   }
 
   {  // Certain GPU features might have been blacklisted.
@@ -568,7 +569,7 @@ WebPreferences RenderViewHostDelegateHelper::GetWebkitPrefs(
     web_prefs.accelerated_compositing_enabled = false;
     web_prefs.accelerated_2d_canvas_enabled = false;
     web_prefs.accelerated_video_enabled = false;
-    web_prefs.accelerated_drawing_enabled = false;
+    web_prefs.accelerated_painting_enabled = false;
     web_prefs.accelerated_plugins_enabled = false;
   }
 
diff --git a/content/common/view_messages.h b/content/common/view_messages.h
index c10934d..c811301 100644
--- a/content/common/view_messages.h
+++ b/content/common/view_messages.h
@@ -219,7 +219,7 @@ IPC_STRUCT_TRAITS_BEGIN(WebPreferences)
   IPC_STRUCT_TRAITS_MEMBER(composite_to_texture_enabled)
   IPC_STRUCT_TRAITS_MEMBER(fixed_position_compositing_enabled)
   IPC_STRUCT_TRAITS_MEMBER(accelerated_2d_canvas_enabled)
-  IPC_STRUCT_TRAITS_MEMBER(accelerated_drawing_enabled)
+  IPC_STRUCT_TRAITS_MEMBER(accelerated_painting_enabled)
   IPC_STRUCT_TRAITS_MEMBER(accelerated_filters_enabled)
   IPC_STRUCT_TRAITS_MEMBER(accelerated_plugins_enabled)
   IPC_STRUCT_TRAITS_MEMBER(accelerated_layers_enabled)
@@ -231,6 +231,7 @@ IPC_STRUCT_TRAITS_BEGIN(WebPreferences)
   IPC_STRUCT_TRAITS_MEMBER(allow_running_insecure_content)
   IPC_STRUCT_TRAITS_MEMBER(enable_scroll_animator)
   IPC_STRUCT_TRAITS_MEMBER(visual_word_movement_enabled)
+  IPC_STRUCT_TRAITS_MEMBER(per_tile_painting_enabled)
 IPC_STRUCT_TRAITS_END()
 
 IPC_STRUCT_TRAITS_BEGIN(WebMenuItem)
diff --git a/content/public/common/content_switches.cc b/content/public/common/content_switches.cc
index 8b0463d..c3bb782 100644
--- a/content/public/common/content_switches.cc
+++ b/content/public/common/content_switches.cc
@@ -170,11 +170,8 @@ const char kDisableWebSockets[]             = "disable-web-sockets";
 // Enable gpu-accelerated 2d canvas.
 const char kEnableAccelerated2dCanvas[]     = "enable-accelerated-2d-canvas";
 
-// Enable hardware accelerated page drawing.
-// Please note that this flag is honored only if chromium is compiled with
-// SKIA_GPU flag, which can be enabled by setting use_skia_gpu variable to 1
-// in build/features_override.gypi.
-const char kEnableAcceleratedDrawing[]      = "enable-accelerated-drawing";
+// Enable hardware accelerated page painting.
+const char kEnableAcceleratedPainting[]     = "enable-accelerated-painting";
 
 // Enable gpu-accelerated SVG/W3C filters.
 const char kEnableAcceleratedFilters[]      = "enable-accelerated-filters";
@@ -559,4 +556,7 @@ const char kUseSystemSSL[]                  = "use-system-ssl";
 const char kRendererCheckFalseTest[]        = "renderer-check-false-test";
 #endif
 
+// Enable per-tile page painting.
+const char kEnablePerTilePainting[]         = "enable-per-tile-painting";
+
 }  // namespace switches
diff --git a/content/public/common/content_switches.h b/content/public/common/content_switches.h
index 4aefed1..6a28d5d 100644
--- a/content/public/common/content_switches.h
+++ b/content/public/common/content_switches.h
@@ -65,7 +65,7 @@ extern const char kDisableSpellcheckAPI[];
 CONTENT_EXPORT extern const char kDisableWebAudio[];
 extern const char kDisableWebSockets[];
 extern const char kEnableAccelerated2dCanvas[];
-CONTENT_EXPORT extern const char kEnableAcceleratedDrawing[];
+CONTENT_EXPORT extern const char kEnableAcceleratedPainting[];
 CONTENT_EXPORT extern const char kEnableAcceleratedFilters[];
 extern const char kEnableAccessibility[];
 extern const char kEnableAccessibilityLogging[];
@@ -180,6 +180,8 @@ extern const char kUseSystemSSL[];
 CONTENT_EXPORT extern const char kRendererCheckFalseTest[];
 #endif
 
+extern const char kEnablePerTilePainting[];
+
 }  // namespace switches
 
 #endif  // CONTENT_PUBLIC_COMMON_CONTENT_SWITCHES_H_
diff --git a/webkit/glue/webpreferences.cc b/webkit/glue/webpreferences.cc
index 71cd35f..4a81945 100644
--- a/webkit/glue/webpreferences.cc
+++ b/webkit/glue/webpreferences.cc
@@ -85,7 +85,7 @@ WebPreferences::WebPreferences()
       accelerated_layers_enabled(false),
       accelerated_video_enabled(false),
       accelerated_2d_canvas_enabled(false),
-      accelerated_drawing_enabled(false),
+      accelerated_painting_enabled(false),
       accelerated_filters_enabled(false),
       accelerated_plugins_enabled(false),
       memory_info_enabled(false),
@@ -96,7 +96,8 @@ WebPreferences::WebPreferences()
       should_print_backgrounds(false),
       enable_scroll_animator(false),
       hixie76_websocket_protocol_enabled(false),
-      visual_word_movement_enabled(false) {
+      visual_word_movement_enabled(false),
+      per_tile_painting_enabled(false) {
 }
 
 WebPreferences::~WebPreferences() {
@@ -279,8 +280,8 @@ void WebPreferences::Apply(WebView* web_view) const {
   // Enable gpu-accelerated 2d canvas if requested on the command line.
   settings->setAccelerated2dCanvasEnabled(accelerated_2d_canvas_enabled);
 
-  // Enable gpu-accelerated drawing if requested on the command line.
-  settings->setAcceleratedDrawingEnabled(accelerated_drawing_enabled);
+  // Enable gpu-accelerated painting if requested on the command line.
+  settings->setAcceleratedPaintingEnabled(accelerated_painting_enabled);
 
   // Enable gpu-accelerated filters if requested on the command line.
   settings->setAcceleratedFiltersEnabled(accelerated_filters_enabled);
@@ -330,5 +331,8 @@ void WebPreferences::Apply(WebView* web_view) const {
       hixie76_websocket_protocol_enabled);
   settings->setVisualWordMovementEnabled(visual_word_movement_enabled);
 
+  // Enable per-tile painting if requested on the command line.
+  settings->setPerTilePaintingEnabled(per_tile_painting_enabled);
+
   WebNetworkStateNotifier::setOnLine(is_online);
 }
diff --git a/webkit/glue/webpreferences.h b/webkit/glue/webpreferences.h
index a7cdfc1..8c3f70fc 100644
--- a/webkit/glue/webpreferences.h
+++ b/webkit/glue/webpreferences.h
@@ -99,7 +99,7 @@ struct WEBKIT_GLUE_EXPORT WebPreferences {
   bool accelerated_layers_enabled;
   bool accelerated_video_enabled;
   bool accelerated_2d_canvas_enabled;
-  bool accelerated_drawing_enabled;
+  bool accelerated_painting_enabled;
   bool accelerated_filters_enabled;
   bool accelerated_plugins_enabled;
   bool memory_info_enabled;
@@ -111,6 +111,7 @@ struct WEBKIT_GLUE_EXPORT WebPreferences {
   bool enable_scroll_animator;
   bool hixie76_websocket_protocol_enabled;
   bool visual_word_movement_enabled;
+  bool per_tile_painting_enabled;
   // We try to keep the default values the same as the default values in
   // chrome, except for the cases where it would require lots of extra work for
   // the embedder to use the same default value.