[Android WebView] Add Internet permission.

Add the android.permission.INTERNET permission to the standalone
WebView's apk, to allow Services belonging to WebView's package to
connect to the internet.

BUG=673280

Review-Url: https://codereview.chromium.org/2562353002
Cr-Commit-Position: refs/heads/master@{#437851}

android_webview/apk/java/AndroidManifest.xml

@@ -15,6 +15,8 @@
     <uses-feature android:name="android.hardware.touchscreen"
             android:required="false"/>
 
+    <uses-permission android:name="android.permission.INTERNET"/>
+
     <application android:label="Android System WebView"
         android:icon="@drawable/icon_webview"
         android:multiArch="true"