Don't put a text shadow on blue buttons in gtk theme mode.

ui/native_theme/common_theme.cc

 // Copyright (c) 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 "ui/native_theme/common_theme.h"
 
 #include "base/logging.h"
 #include "grit/ui_resources.h"
 #include "third_party/skia/include/core/SkCanvas.h"
 #include "ui/base/resource/resource_bundle.h"
@@ skipping 21 matching lines @@
 const SkColor kEnabledMenuItemForegroundColor = SK_ColorBLACK;
 const SkColor kDisabledMenuItemForegroundColor = SkColorSetRGB(161, 161, 146);
 const SkColor kHoverMenuItemBackgroundColor =
     SkColorSetARGB(204, 255, 255, 255);
 // Button:
 const SkColor kButtonHoverBackgroundColor = SkColorSetRGB(0xEA, 0xEA, 0xEA);
 const SkColor kBlueButtonEnabledColor = SK_ColorWHITE;
 const SkColor kBlueButtonDisabledColor = SK_ColorWHITE;
 const SkColor kBlueButtonPressedColor = SK_ColorWHITE;
 const SkColor kBlueButtonHoverColor = SK_ColorWHITE;
+const SkColor kBlueButtonShadowColor = SkColorSetRGB(0x53, 0x8C, 0xEA);
 
 }  // namespace
 
 namespace ui {
 
 bool CommonThemeGetSystemColor(NativeTheme::ColorId color_id, SkColor* color) {
   switch (color_id) {
     // MenuItem
     case NativeTheme::kColorId_MenuBorderColor:
       *color = kMenuBorderColor;
@@ skipping 42 matching lines @@
       *color = kBlueButtonEnabledColor;
       break;
     case NativeTheme::kColorId_BlueButtonDisabledColor:
       *color = kBlueButtonDisabledColor;
       break;
     case NativeTheme::kColorId_BlueButtonPressedColor:
       *color = kBlueButtonPressedColor;
       break;
     case NativeTheme::kColorId_BlueButtonHoverColor:
       *color = kBlueButtonHoverColor;
+    case NativeTheme::kColorId_BlueButtonShadowColor:
+      *color = kBlueButtonShadowColor;
       break;
     default:
       return false;
   }
 
   if (gfx::IsInvertedColorScheme()) {
     switch (color_id) {
       case NativeTheme::kColorId_FocusedMenuItemBackgroundColor:
         *color = kMenuInvertedSchemeHighlightBackgroundColor;
         break;
@@ skipping 90 matching lines @@
 scoped_ptr<gfx::Canvas> CommonThemeCreateCanvas(SkCanvas* sk_canvas) {
   // TODO(pkotwicz): Do something better and don't infer device
   // scale factor from canvas scale.
   SkMatrix m = sk_canvas->getTotalMatrix();
   float device_scale = static_cast<float>(SkScalarAbs(m.getScaleX()));
   return scoped_ptr<gfx::Canvas>(
       gfx::Canvas::CreateCanvasWithoutScaling(sk_canvas, device_scale));
 }
 
 }  // namespace ui