WebView: Add channel info for UMA

android_webview/java/src/org/chromium/android_webview/AwMetricsServiceClient.java

 // Copyright 2015 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.android_webview;
 
 import android.content.Context;
 import android.content.pm.ApplicationInfo;
 import android.content.pm.PackageManager;
 
@@ skipping 61 matching lines @@
 
     @CalledByNative
     public static void nativeInitialized() {
         ThreadUtils.assertOnUiThread();
         sIsClientReady = true;
         if (sShouldEnable) {
             nativeSetMetricsEnabled(true);
         }
     }
 
+    @CalledByNative
+    public static String getWebViewPackageName() {
+        return AwBrowserProcess.getWebViewPackageName();
+    }
+
     public static native void nativeSetMetricsEnabled(boolean enabled);
 }