Remove Label::PaintText overrides.

This is simple cleanup in preparation for a Label rewrite.
These overrides were supplying an extra gfx::Canvas flag.
Instead, add an explicit label flag for NO_SUBPIXEL_RENDERING.
Update some callers and the unit test.

TODO(followup): Update more Label::SetBackgroundColor callers.

BUG=240037
TEST=No exit warning or sticky keys label rendering changes.
R=sky@chromium.org

Review URL: https://codereview.chromium.org/341713002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@278213 0039d316-1c4b-4281-b951-d872f2087c98

8 files changed, 27 insertions, 56 deletions

diff --git a/ash/accelerators/exit_warning_handler.cc b/ash/accelerators/exit_warning_handler.cc
index d2dc0f5..d01466b 100644
--- a/ash/accelerators/exit_warning_handler.cc
+++ b/ash/accelerators/exit_warning_handler.cc
@@ -38,27 +38,6 @@ const int kWindowCornerRadius = 2;
 const int kHorizontalMarginAroundText = 100;
 const int kVerticalMarginAroundText = 100;
 
-class ExitWarningLabel : public views::Label {
- public:
-  ExitWarningLabel() {}
-
-  virtual ~ExitWarningLabel() {}
-
- private:
-  virtual void PaintText(gfx::Canvas* canvas,
-                         const base::string16& text,
-                         const gfx::Rect& text_bounds,
-                         int flags) OVERRIDE {
-    // Turn off subpixel rendering.
-    views::Label::PaintText(canvas,
-                            text,
-                            text_bounds,
-                            flags | gfx::Canvas::NO_SUBPIXEL_RENDERING);
-  }
-
-  DISALLOW_COPY_AND_ASSIGN(ExitWarningLabel);
-};
-
 class ExitWarningWidgetDelegateView : public views::WidgetDelegateView {
  public:
   ExitWarningWidgetDelegateView() : text_width_(0), width_(0), height_(0) {
@@ -77,13 +56,14 @@ class ExitWarningWidgetDelegateView : public views::WidgetDelegateView {
     text_width_ = gfx::GetStringWidth(text_, font_list);
     width_ = text_width_ + kHorizontalMarginAroundText;
     height_ = font_list.GetHeight() + kVerticalMarginAroundText;
-    views::Label* label = new ExitWarningLabel;
+    views::Label* label = new views::Label();
     label->SetText(text_);
     label->SetHorizontalAlignment(gfx::ALIGN_CENTER);
     label->SetFontList(font_list);
     label->SetEnabledColor(kTextColor);
     label->SetDisabledColor(kTextColor);
     label->SetAutoColorReadabilityEnabled(false);
+    label->set_subpixel_rendering_enabled(false);
     AddChildView(label);
     SetLayoutManager(new views::FillLayout);
   }
diff --git a/ash/sticky_keys/sticky_keys_overlay.cc b/ash/sticky_keys/sticky_keys_overlay.cc
index 7720ad6..c68f227 100644
--- a/ash/sticky_keys/sticky_keys_overlay.cc
+++ b/ash/sticky_keys/sticky_keys_overlay.cc
@@ -54,12 +54,6 @@ class StickyKeyOverlayLabel : public views::Label {
   void SetKeyState(StickyKeyState state);
 
  private:
-  // views::Label overrides:
-  virtual void PaintText(gfx::Canvas* canvas,
-                         const base::string16& text,
-                         const gfx::Rect& text_bounds,
-                         int flags) OVERRIDE;
-
   StickyKeyState state_;
 
   DISALLOW_COPY_AND_ASSIGN(StickyKeyOverlayLabel);
@@ -76,6 +70,7 @@ StickyKeyOverlayLabel::StickyKeyOverlayLabel(const std::string& key_name)
   SetFocusable(false);
   SetEnabledColor(SkColorSetARGB(0x80, 0xFF, 0xFF, 0xFF));
   SetDisabledColor(SkColorSetARGB(0x80, 0xFF, 0xFF, 0xFF));
+  set_subpixel_rendering_enabled(false);
 }
 
 StickyKeyOverlayLabel::~StickyKeyOverlayLabel() {
@@ -104,19 +99,8 @@ void StickyKeyOverlayLabel::SetKeyState(StickyKeyState state) {
   SetFontList(font_list().DeriveWithStyle(style));
 }
 
-void StickyKeyOverlayLabel::PaintText(gfx::Canvas* canvas,
-                                      const base::string16& text,
-                                      const gfx::Rect& text_bounds,
-                                      int flags) {
-  views::Label::PaintText(canvas,
-                          text,
-                          text_bounds,
-                          flags | gfx::Canvas::NO_SUBPIXEL_RENDERING);
-}
-
-
 ///////////////////////////////////////////////////////////////////////////////
-//  StickyKeyOverlayLabel
+//  StickyKeysOverlayView
 class StickyKeysOverlayView : public views::WidgetDelegateView {
  public:
   StickyKeysOverlayView();
diff --git a/chrome/browser/ui/views/frame/opaque_browser_frame_view.cc b/chrome/browser/ui/views/frame/opaque_browser_frame_view.cc
index e5ddc9a..28b1dbc 100644
--- a/chrome/browser/ui/views/frame/opaque_browser_frame_view.cc
+++ b/chrome/browser/ui/views/frame/opaque_browser_frame_view.cc
@@ -141,9 +141,7 @@ OpaqueBrowserFrameView::OpaqueBrowserFrameView(BrowserFrame* frame,
       gfx::FontList(BrowserFrame::GetTitleFontList()));
   window_title_->SetVisible(browser_view->ShouldShowWindowTitle());
   window_title_->SetEnabledColor(SK_ColorWHITE);
-  // TODO(msw): Use a transparent background color as a workaround to use the
-  // gfx::Canvas::NO_SUBPIXEL_RENDERING flag and avoid some visual artifacts.
-  window_title_->SetBackgroundColor(0x00000000);
+  window_title_->set_subpixel_rendering_enabled(false);
   window_title_->SetHorizontalAlignment(gfx::ALIGN_LEFT);
   window_title_->set_id(VIEW_ID_WINDOW_TITLE);
   AddChildView(window_title_);
diff --git a/chrome/browser/ui/views/frame/opaque_browser_frame_view_layout_unittest.cc b/chrome/browser/ui/views/frame/opaque_browser_frame_view_layout_unittest.cc
index 48dce3e..9e94e7f 100644
--- a/chrome/browser/ui/views/frame/opaque_browser_frame_view_layout_unittest.cc
+++ b/chrome/browser/ui/views/frame/opaque_browser_frame_view_layout_unittest.cc
@@ -207,7 +207,7 @@ class OpaqueBrowserFrameViewLayoutTest : public views::ViewsTestBase {
     window_title_ = new views::Label(delegate_->GetWindowTitle());
     window_title_->SetVisible(delegate_->ShouldShowWindowTitle());
     window_title_->SetEnabledColor(SK_ColorWHITE);
-    window_title_->SetBackgroundColor(0x00000000);
+    window_title_->set_subpixel_rendering_enabled(false);
     window_title_->SetHorizontalAlignment(gfx::ALIGN_LEFT);
     window_title_->set_id(VIEW_ID_WINDOW_TITLE);
     root_view_->AddChildView(window_title_);
diff --git a/ui/views/controls/label.cc b/ui/views/controls/label.cc
index 6aed59f..00bc751 100644
--- a/ui/views/controls/label.cc
+++ b/ui/views/controls/label.cc
@@ -383,6 +383,7 @@ void Label::OnNativeThemeChanged(const ui::NativeTheme* theme) {
 void Label::Init(const base::string16& text, const gfx::FontList& font_list) {
   font_list_ = font_list;
   enabled_color_set_ = disabled_color_set_ = background_color_set_ = false;
+  subpixel_rendering_enabled_ = true;
   auto_color_readability_ = true;
   UpdateColorsFromTheme(ui::NativeTheme::instance());
   horizontal_alignment_ = gfx::ALIGN_CENTER;
@@ -439,7 +440,7 @@ int Label::ComputeDrawStringFlags() const {
   int flags = 0;
 
   // We can't use subpixel rendering if the background is non-opaque.
-  if (SkColorGetA(background_color_) != 0xFF)
+  if (SkColorGetA(background_color_) != 0xFF || !subpixel_rendering_enabled_)
     flags |= gfx::Canvas::NO_SUBPIXEL_RENDERING;
 
   if (directionality_mode_ == gfx::DIRECTIONALITY_FORCE_LTR) {
diff --git a/ui/views/controls/label.h b/ui/views/controls/label.h
index cbb12cb..f41ce85 100644
--- a/ui/views/controls/label.h
+++ b/ui/views/controls/label.h
@@ -62,6 +62,12 @@ class VIEWS_EXPORT Label : public View {
   // Set drop shadows underneath the text.
   void set_shadows(const gfx::ShadowValues& shadows) { shadows_ = shadows; }
 
+  // Sets whether subpixel rendering is used; the default is true, but this
+  // feature also requires an opaque background color.
+  void set_subpixel_rendering_enabled(bool subpixel_rendering_enabled) {
+    subpixel_rendering_enabled_ = subpixel_rendering_enabled;
+  }
+
   // Set the color of a halo on the painted text (use transparent for none).
   void set_halo_color(SkColor halo_color) { halo_color_ = halo_color; }
 
@@ -218,6 +224,7 @@ class VIEWS_EXPORT Label : public View {
   bool disabled_color_set_;
   bool background_color_set_;
 
+  bool subpixel_rendering_enabled_;
   bool auto_color_readability_;
   mutable gfx::Size text_size_;
   mutable bool text_size_valid_;
diff --git a/ui/views/controls/label_unittest.cc b/ui/views/controls/label_unittest.cc
index 1ff16b4..8b16d0f 100644
--- a/ui/views/controls/label_unittest.cc
+++ b/ui/views/controls/label_unittest.cc
@@ -862,18 +862,19 @@ TEST(LabelTest, DrawMultiLineStringInRTL) {
   base::i18n::SetICUDefaultLocale(locale);
 }
 
-// Check that we disable subpixel rendering when a transparent background is
-// being used.
+// Ensure the subpixel rendering flag and background color alpha are respected.
 TEST(LabelTest, DisableSubpixelRendering) {
   Label label;
   label.SetBackgroundColor(SK_ColorWHITE);
-  EXPECT_EQ(
-      0, label.ComputeDrawStringFlags() & gfx::Canvas::NO_SUBPIXEL_RENDERING);
-
+  const int flag = gfx::Canvas::NO_SUBPIXEL_RENDERING;
+  EXPECT_EQ(0, label.ComputeDrawStringFlags() & flag);
+  label.set_subpixel_rendering_enabled(false);
+  EXPECT_EQ(flag, label.ComputeDrawStringFlags() & flag);
+  label.set_subpixel_rendering_enabled(true);
+  EXPECT_EQ(0, label.ComputeDrawStringFlags() & flag);
+  // Text cannot be drawn with subpixel rendering on transparent backgrounds.
   label.SetBackgroundColor(SkColorSetARGB(64, 255, 255, 255));
-  EXPECT_EQ(
-      gfx::Canvas::NO_SUBPIXEL_RENDERING,
-      label.ComputeDrawStringFlags() & gfx::Canvas::NO_SUBPIXEL_RENDERING);
+  EXPECT_EQ(flag, label.ComputeDrawStringFlags() & flag);
 }
 
 // Check that labels support GetTooltipHandlerForPoint.
diff --git a/ui/views/controls/textfield/textfield.cc b/ui/views/controls/textfield/textfield.cc
index 2dd6fb4..a175990 100644
--- a/ui/views/controls/textfield/textfield.cc
+++ b/ui/views/controls/textfield/textfield.cc
@@ -992,8 +992,8 @@ void Textfield::WriteDragDataForView(View* sender,
   const base::string16& selected_text(GetSelectedText());
   data->SetString(selected_text);
   Label label(selected_text, GetFontList());
-  const SkColor background = GetBackgroundColor();
-  label.SetBackgroundColor(SkColorSetA(background, SK_AlphaTRANSPARENT));
+  label.SetBackgroundColor(GetBackgroundColor());
+  label.set_subpixel_rendering_enabled(false);
   gfx::Size size(label.GetPreferredSize());
   gfx::NativeView native_view = GetWidget()->GetNativeView();
   gfx::Display display = gfx::Screen::GetScreenFor(native_view)->
@@ -1005,7 +1005,7 @@ void Textfield::WriteDragDataForView(View* sender,
   label.SetEnabledColor(GetTextColor());
 #if defined(OS_LINUX) && !defined(OS_CHROMEOS)
   // Desktop Linux Aura does not yet support transparency in drag images.
-  canvas->DrawColor(background);
+  canvas->DrawColor(GetBackgroundColor());
 #endif
   label.Paint(canvas.get(), views::CullSet());
   const gfx::Vector2d kOffset(-15, 0);