[Chromecast] Add background color flag.

Adds a flag (--cast-app-background-color) that changes the background
color used when displaying web apps. This color is often shown briefly
before Chromium renders a web app.

Bug: internal b/70181260
Test: use flag on ATV
Change-Id: I3bc0989aeabbf639116c1b30fffb11f66b56c4cd
Reviewed-on: https://chromium-review.googlesource.com/897466
Commit-Queue: Thoren Paulson <thoren@chromium.org>
Reviewed-by: Stephen Lanham <slan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#540340}

chromecast/base/BUILD.gn

@@ -294,6 +294,7 @@ if (is_android) {
 
       # TODO(sanfin): Move these files to another target.
       "$java_src_dir/org/chromium/chromecast/base/CastSettingsManager.java",
+      "$java_src_dir/org/chromium/chromecast/base/CastSwitches.java",
       "$java_src_dir/org/chromium/chromecast/base/ChromecastConfigAndroid.java",
       "$java_src_dir/org/chromium/chromecast/base/DumpstateWriter.java",
       "$java_src_dir/org/chromium/chromecast/base/SystemTimeChangeNotifierAndroid.java",

chromecast/base/chromecast_switches.cc

@@ -133,6 +133,9 @@ const char kDesktopWindow1080p[] = "desktop-window-1080p";
 // Enables input event handling by the window manager.
 const char kEnableInput[] = "enable-input";
 
+// Background color used when Chromium hasn't rendered anything yet.
+const char kCastAppBackgroundColor[] = "cast-app-background-color";
+
 }  // namespace switches
 
 namespace chromecast {
@@ -187,4 +190,24 @@ int GetSwitchValueNonNegativeInt(const std::string& switch_name,
   return value;
 }
 
+uint32_t GetSwitchValueColor(const std::string& switch_name,
+                             const uint32_t default_value) {
+  const base::CommandLine* command_line =
+      base::CommandLine::ForCurrentProcess();
+  if (!command_line->HasSwitch(switch_name)) {
+    return default_value;
+  }
+
+  uint32_t arg_value = 0;
+  if (!base::HexStringToUInt(
+          command_line->GetSwitchValueASCII(switch_name).substr(1),
+          &arg_value)) {
+    LOG(ERROR) << "Invalid value for " << switch_name << " ("
+               << command_line->GetSwitchValueASCII(switch_name)
+               << "), using default.";
+    return default_value;
+  }
+  return arg_value;
+}
+
 }  // namespace chromecast

chromecast/base/chromecast_switches.h

@@ -5,6 +5,7 @@
 #ifndef CHROMECAST_BASE_CHROMECAST_SWITCHES_H_
 #define CHROMECAST_BASE_CHROMECAST_SWITCHES_H_
 
+#include <cstdint>
 #include <string>
 
 #include "build/build_config.h"
@@ -73,6 +74,9 @@ extern const char kDesktopWindow1080p[];
 // UI switches
 extern const char kEnableInput[];
 
+// Background color used when Chromium hasn't rendered anything yet.
+extern const char kCastAppBackgroundColor[];
+
 }  // namespace switches
 
 namespace chromecast {
@@ -96,6 +100,10 @@ int GetSwitchValueInt(const std::string& switch_name, const int default_value);
 int GetSwitchValueNonNegativeInt(const std::string& switch_name,
                                  const int default_value);
 
+// Gets a color value from the format "#AARRGGBB" (hex).
+uint32_t GetSwitchValueColor(const std::string& switch_name,
+                             const uint32_t default_value);
+
 }  // namespace chromecast
 
 #endif  // CHROMECAST_BASE_CHROMECAST_SWITCHES_H_

chromecast/base/java/src/org/chromium/chromecast/base/CastSwitches.java

+// Copyright 2018 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.
+
+package org.chromium.chromecast.base;
+
+import android.graphics.Color;
+
+import org.chromium.base.CommandLine;
+import org.chromium.base.Log;
+
+/**
+ * Contains all of the command line switches that are specific to Chromecast on
+ * on Android.
+ */
+public abstract class CastSwitches {
+    private static final String TAG = "cr_CastSwitches";
+
+    // Background color to use when chromium hasn't rendered anything yet. This will often be
+    // displayed briefly when loading a Cast app. Format is a #ARGB in hex. (Black: #FF000000,
+    // Green: #FF009000, and so on)
+    public static final String CAST_APP_BACKGROUND_COLOR = "cast-app-background-color";
+
+    public static int getSwitchValueColor(String switchName, int defaultValue) {
+        String colorString = CommandLine.getInstance().getSwitchValue(switchName);
+        try {
+            if (colorString != null) {
+                return Color.parseColor(colorString);
+            }
+        } catch (IllegalArgumentException e) {
+            Log.e(TAG, "Invalid value for %s (%s). Using default.",
+                    CastSwitches.CAST_APP_BACKGROUND_COLOR, colorString);
+        }
+        return defaultValue;
+    }
+
+    // Prevent instantiation
+    private CastSwitches() {}
+}

chromecast/browser/android/apk/src/org/chromium/chromecast/shell/CastWebContentsSurfaceHelper.java

@@ -17,6 +17,7 @@ import android.widget.FrameLayout;
 import org.chromium.base.ContextUtils;
 import org.chromium.base.Log;
 import org.chromium.base.annotations.JNINamespace;
+import org.chromium.chromecast.base.CastSwitches;
 import org.chromium.chromecast.base.Controller;
 import org.chromium.chromecast.base.Unit;
 import org.chromium.components.content_view.ContentView;
@@ -76,6 +77,8 @@ class CastWebContentsSurfaceHelper {
         mHostActivity = hostActivity;
         mShowInFragment = showInFragment;
         mCastWebContentsLayout = castWebContentsLayout;
+        mCastWebContentsLayout.setBackgroundColor(CastSwitches.getSwitchValueColor(
+                CastSwitches.CAST_APP_BACKGROUND_COLOR, Color.BLACK));
         mHandler = new Handler();
         mAudioManager = CastAudioManager.getAudioManager(getActivity());
         mAudioManager.requestAudioFocusWhen(
@@ -178,9 +181,10 @@ class CastWebContentsSurfaceHelper {
             }
         };
         mContentViewRenderView.onNativeLibraryLoaded(mWindow);
-        // Setting the background color to black avoids rendering a white splash screen
+        // Setting the background color avoids rendering a white splash screen
         // before the players are loaded. See https://crbug/307113 for details.
-        mContentViewRenderView.setSurfaceViewBackgroundColor(Color.BLACK);
+        mContentViewRenderView.setSurfaceViewBackgroundColor(CastSwitches.getSwitchValueColor(
+                CastSwitches.CAST_APP_BACKGROUND_COLOR, Color.BLACK));
 
         mCastWebContentsLayout.addView(mContentViewRenderView,
                 new FrameLayout.LayoutParams(FrameLayout.LayoutParams.MATCH_PARENT,

chromecast/browser/cast_web_view_default.cc

@@ -10,6 +10,7 @@
 #include "base/logging.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "chromecast/base/cast_features.h"
+#include "chromecast/base/chromecast_switches.h"
 #include "chromecast/base/metrics/cast_metrics_helper.h"
 #include "chromecast/browser/cast_browser_process.h"
 #include "chromecast/browser/cast_web_contents_manager.h"
@@ -267,8 +268,10 @@ void CastWebViewDefault::RenderViewCreated(
   content::RenderWidgetHostView* view =
       render_view_host->GetWidget()->GetView();
   if (view) {
-    view->SetBackgroundColor(transparent_ ? SK_ColorTRANSPARENT
-                                          : SK_ColorBLACK);
+    view->SetBackgroundColor(
+        transparent_ ? SK_ColorTRANSPARENT
+                     : chromecast::GetSwitchValueColor(
+                           switches::kCastAppBackgroundColor, SK_ColorBLACK));
   }
 }
 

chromecast/renderer/cast_content_renderer_client.cc

@@ -57,14 +57,6 @@
 namespace chromecast {
 namespace shell {
 
-namespace {
-
-// Default background color to set for WebViews. WebColor is in ARGB format
-// though the comment of WebColor says it is in RGBA.
-const blink::WebColor kColorBlack = 0xFF000000;
-
-}  // namespace
-
 CastContentRendererClient::CastContentRendererClient()
     : supported_profiles_(new media::SupportedCodecProfileLevelsMemo()),
       app_media_capabilities_observer_binding_(this),
@@ -146,7 +138,8 @@ void CastContentRendererClient::RenderViewCreated(
   blink::WebView* webview = render_view->GetWebView();
   if (webview) {
     if (auto* web_frame_widget = render_view->GetWebFrameWidget())
-      web_frame_widget->SetBaseBackgroundColor(kColorBlack);
+      web_frame_widget->SetBaseBackgroundColor(chromecast::GetSwitchValueColor(
+          switches::kCastAppBackgroundColor, SK_ColorBLACK));
 
     // Disable application cache as Chromecast doesn't support off-line
     // application running.