Add the plumbing to enable DRP

android_webview/browser/aw_browser_context.cc

Index: android_webview/browser/aw_browser_context.cc
diff --git a/android_webview/browser/aw_browser_context.cc b/android_webview/browser/aw_browser_context.cc
index e4a2a1d08a700ae9d93eb84d36710a02014a3059..248ade1d2d3dd8506354167950bd43057e21adc2 100644
--- a/android_webview/browser/aw_browser_context.cc
+++ b/android_webview/browser/aw_browser_context.cc
@@ -41,6 +41,9 @@ AwBrowserContext* g_browser_context = NULL;
 
 }  // namespace
 
+// Data reduction proxy is disabled by default.
+bool AwBrowserContext::data_reduction_proxy_enabled_ = false;
+
 AwBrowserContext::AwBrowserContext(
     const FilePath path,
     JniDependencyFactory* native_factory)
@@ -73,6 +76,22 @@ AwBrowserContext* AwBrowserContext::FromWebContents(
   return static_cast<AwBrowserContext*>(web_contents->GetBrowserContext());
 }
 
+// static
+void AwBrowserContext::SetDataReductionProxyEnabled(bool enabled) {
+  // Cache the setting value. It is possible that data reduction proxy is
+  // not created yet.
+  data_reduction_proxy_enabled_ = enabled;
+  AwBrowserContext* context = AwBrowserContext::GetDefault();
+  // Can't enable Data reduction proxy if user pref service is not ready.
+  if (context == NULL || context->user_pref_service_.get() == NULL)
+    return;
+  DataReductionProxySettings* proxy_settings =
+      context->GetDataReductionProxySettings();
+  if (proxy_settings == NULL)
+    return;
+  proxy_settings->SetDataReductionProxyEnabled(data_reduction_proxy_enabled_);
+}
+
 void AwBrowserContext::PreMainMessageLoopRun() {
   cookie_store_ = CreateCookieStore(this);
   DataReductionProxySettings::SetAllowed(true);
@@ -169,9 +188,8 @@ void AwBrowserContext::CreateUserPrefServiceIfNecessary() {
       user_pref_service_.get(),
       GetRequestContext());
 
-  //TODO(sgurun): Attach this to the API. It is currently hard coded in a
-  // disabled state.
-  data_reduction_proxy_settings_->SetDataReductionProxyEnabled(false);
+  data_reduction_proxy_settings_->SetDataReductionProxyEnabled(
+      data_reduction_proxy_enabled_);
 }
 
 base::FilePath AwBrowserContext::GetPath() const {