fix text color of BlueButton on GTK-theme-mode Linux Aura.

ui/views/controls/button/blue_button.cc

Index: ui/views/controls/button/blue_button.cc
diff --git a/ui/views/controls/button/blue_button.cc b/ui/views/controls/button/blue_button.cc
index ddf7e37b99e3371f4530c72edfdf3fbe245d1ea5..a7dda6dcee3da954e5afc576eff4b00d30a00d8e 100644
--- a/ui/views/controls/button/blue_button.cc
+++ b/ui/views/controls/button/blue_button.cc
@@ -11,8 +11,7 @@
 
 namespace {
 
-// Default text and shadow colors for the blue button.
-const SkColor kBlueButtonTextColor = SK_ColorWHITE;
+// Default shadow color for the blue button.
 const SkColor kBlueButtonShadowColor = SkColorSetRGB(0x53, 0x8C, 0xEA);
 
 }  // namespace
@@ -34,8 +33,20 @@ BlueButton::~BlueButton() {}
 void BlueButton::ResetColorsFromNativeTheme() {
   LabelButton::ResetColorsFromNativeTheme();
   if (!gfx::IsInvertedColorScheme()) {
-    for (size_t state = STATE_NORMAL; state < STATE_COUNT; ++state)
-      SetTextColor(static_cast<ButtonState>(state), kBlueButtonTextColor);
+    SetTextColor(STATE_NORMAL, GetNativeTheme()->
+        GetSystemColor(
+            ui::NativeTheme::kColorId_CallToActionButtonEnabledColor));
+    SetTextColor(STATE_HOVERED, GetNativeTheme()->
+        GetSystemColor(
+            ui::NativeTheme::kColorId_CallToActionButtonHoverColor));
+    SetTextColor(STATE_PRESSED, GetNativeTheme()->
+        GetSystemColor(
+            ui::NativeTheme::kColorId_CallToActionButtonHighlightColor));
+    SetTextColor(STATE_DISABLED, GetNativeTheme()->
+        GetSystemColor(
+            ui::NativeTheme::kColorId_CallToActionButtonDisabledColor));
+
+    // TODO(estade): this is not great on system themes.

[msw, 2014/06/02 21:06:20]

Perhaps we could use a partially transparent version of the text color? That's
probably how the original shadow color was calculated (expecting white on blue).

[Evan Stade, 2014/06/02 22:18:14]

I'd be inclined to have no shadow on gtk system themes (fully transparent),
while leaving this color as the default in fallback theme. But exploring all the
options is a TODO.

     label()->SetShadowColors(kBlueButtonShadowColor, kBlueButtonShadowColor);
     label()->SetShadowOffset(0, 1);
   }