WebView: Create UMA uploader

android_webview/java/src/org/chromium/android_webview/PlatformServiceBridge.java

Index: android_webview/java/src/org/chromium/android_webview/PlatformServiceBridge.java
diff --git a/android_webview/java/src/org/chromium/android_webview/PlatformServiceBridge.java b/android_webview/java/src/org/chromium/android_webview/PlatformServiceBridge.java
index 038e6ea2ed331057084c4370b62956afe1e44a48..0ced33e7389f288c0330013f211c76d31f63f0a4 100644
--- a/android_webview/java/src/org/chromium/android_webview/PlatformServiceBridge.java
+++ b/android_webview/java/src/org/chromium/android_webview/PlatformServiceBridge.java
@@ -68,4 +68,7 @@ public class PlatformServiceBridge {
         ThreadUtils.assertOnUiThread();
         callback.onReceiveValue(false);
     }
+
+    // Takes an uncompressed, serialized UMA proto and logs it via a platform-specific mechanism.
+    public void logMetrics(byte[] data) {}
 }