Always use a white theme for System App popup settings pages

Bug: 1033339
Change-Id: Ia8f0c24deb742d04b0a10bb4fbcb4c3322ea1547
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2065776
Commit-Queue: Joel Hockey <joelhockey@chromium.org>
Reviewed-by: Alan Cutter <alancutter@chromium.org>
Cr-Commit-Position: refs/heads/master@{#742992}

chrome/browser/ui/web_applications/app_browser_controller.cc

@@ -292,6 +292,10 @@ void AppBrowserController::DidChangeThemeColor() {
 }
 
 base::Optional<SkColor> AppBrowserController::GetThemeColor() const {
+  // System App popus (settings pages) always use white theme.
+  if (system_app_type_ && browser_->is_type_app_popup())
+    return SK_ColorWHITE;
+
   base::Optional<SkColor> result;
   // HTML meta theme-color tag overrides manifest theme_color, see spec:
   // https://www.w3.org/TR/appmanifest/#theme_color-member

chrome/browser/ui/web_applications/app_browser_controller_browsertest.cc

@@ -101,6 +101,16 @@ class AppBrowserControllerBrowserTest : public InProcessBrowserTest {
         tabbed_app_url_));
   }
 
+  void InstallAndLaunchMockPopup() {
+    test_system_web_app_installation_->WaitForAppInstall();
+    auto params = web_app::CreateSystemWebAppLaunchParams(
+        browser()->profile(), test_system_web_app_installation_->GetType());
+    params->disposition = WindowOpenDisposition::NEW_POPUP;
+    app_browser_ = web_app::LaunchSystemWebApp(
+        browser()->profile(), test_system_web_app_installation_->GetType(),
+        test_system_web_app_installation_->GetAppUrl(), *params);
+  }
+
   GURL GetActiveTabURL() {
     return app_browser_->tab_strip_model()
         ->GetActiveWebContents()
@@ -188,4 +198,10 @@ IN_PROC_BROWSER_TEST_F(AppBrowserControllerBrowserTest, TabLoadNoThemeChange) {
   EXPECT_EQ(GetTabColor(app_browser_), SK_ColorGREEN);
 }
 
+IN_PROC_BROWSER_TEST_F(AppBrowserControllerBrowserTest,
+                       WhiteThemeForSystemAppPopup) {
+  InstallAndLaunchMockPopup();
+  EXPECT_EQ(app_browser_->app_controller()->GetThemeColor(), SK_ColorWHITE);
+}
+
 }  // namespace web_app