Make COLOR_CONTROL_BACKGROUND customizable from a theme extension

chrome/browser/themes/browser_theme_pack_unittest.cc

Index: chrome/browser/themes/browser_theme_pack_unittest.cc
diff --git a/chrome/browser/themes/browser_theme_pack_unittest.cc b/chrome/browser/themes/browser_theme_pack_unittest.cc
index c79c6c2031c1cfcb86b6a8d2b67b8b1a96e4d3e4..c1ee1e22706816947657d78d04a6dc2442d45ad0 100644
--- a/chrome/browser/themes/browser_theme_pack_unittest.cc
+++ b/chrome/browser/themes/browser_theme_pack_unittest.cc
@@ -213,6 +213,10 @@ class BrowserThemePackTest : public ::testing::Test {
                                &color));
     EXPECT_EQ(SK_ColorBLACK, color);
 
+    EXPECT_TRUE(
+        pack->GetColor(ThemeProperties::COLOR_CONTROL_BACKGROUND, &color));
+    EXPECT_EQ(SkColorSetRGB(10, 234, 123), color);
+
     EXPECT_TRUE(pack->GetColor(ThemeProperties::COLOR_NTP_BACKGROUND,
                                &color));
     EXPECT_EQ(SkColorSetRGB(57, 137, 194), color);
@@ -248,8 +252,6 @@ class BrowserThemePackTest : public ::testing::Test {
 #endif
 
     // Make sure we don't have phantom data.
-    EXPECT_FALSE(pack->GetColor(ThemeProperties::COLOR_CONTROL_BACKGROUND,
-                                &color));
     EXPECT_FALSE(pack->GetTint(ThemeProperties::TINT_FRAME, &actual));
   }