Start caching the theme color in web_contents

content/browser/web_contents/web_contents_android.cc

Index: content/browser/web_contents/web_contents_android.cc
diff --git a/content/browser/web_contents/web_contents_android.cc b/content/browser/web_contents/web_contents_android.cc
index 5a89df69f203be45e6a06a4d23745eb3be6a0eba..07d66310c5c166cf565545e69da94d202a2bd8ca 100644
--- a/content/browser/web_contents/web_contents_android.cc
+++ b/content/browser/web_contents/web_contents_android.cc
@@ -165,6 +165,13 @@ jint WebContentsAndroid::GetBackgroundColor(JNIEnv* env, jobject obj) {
   return rwhva->GetCachedBackgroundColor();
 }
 
+jint WebContentsAndroid::GetThemeColor(JNIEnv* env, jobject obj) {
+  RenderWidgetHostViewAndroid* rwhva = GetRenderWidgetHostViewAndroid();
+  if (!rwhva)
+    return SK_ColorWHITE;
+  return rwhva->GetThemeColor();
+}
+
 ScopedJavaLocalRef<jstring> WebContentsAndroid::GetURL(JNIEnv* env,
                                                        jobject obj) const {
   return ConvertUTF8ToJavaString(env, web_contents_->GetURL().spec());