Add ExternalPrerenderRequestHandler and related API

chrome/android/java/src/org/chromium/chrome/browser/prerender/ExternalPrerenderRequestHandler.java

Index: chrome/android/java/src/org/chromium/chrome/browser/prerender/ExternalPrerenderRequestHandler.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/prerender/ExternalPrerenderRequestHandler.java b/chrome/android/java/src/org/chromium/chrome/browser/prerender/ExternalPrerenderRequestHandler.java
new file mode 100644
index 0000000000000000000000000000000000000000..bac54574dd38a5ae28c600fd08935f9c2855bf05
--- /dev/null
+++ b/chrome/android/java/src/org/chromium/chrome/browser/prerender/ExternalPrerenderRequestHandler.java
@@ -0,0 +1,45 @@
+// Copyright (c) 2013 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.chrome.browser.prerender;
+
+import org.chromium.base.JNINamespace;
+import org.chromium.chrome.browser.profiles.Profile;
+
+/**
+ * A handler class for prerender requests coming from  other applications.
+ */
+@JNINamespace("prerender")
+public class ExternalPrerenderRequestHandler {
+
+    private int mNativeExternalPrerenderRequestHandler;
+
+    public ExternalPrerenderRequestHandler() {
+        mNativeExternalPrerenderRequestHandler = nativeInit();
+    }
+
+    public int addPrerender(Profile profile, String url, String referrer, int width, int height) {
+        if (mNativeExternalPrerenderRequestHandler == 0) return 0;
+        return nativeAddPrerender(
+                mNativeExternalPrerenderRequestHandler, profile, url, referrer, width, height);
+    }
+
+    public void cancelCurrentPrerender() {
+        if (mNativeExternalPrerenderRequestHandler == 0) return;
+        nativeCancelCurrentPrerender(mNativeExternalPrerenderRequestHandler);
+    }
+
+    public static boolean hasPrerenderedUrl(Profile profile, String url, int webContentsPtr)  {
+        return nativeHasPrerenderedUrl(profile, url, webContentsPtr);
+    }
+
+    private static native int nativeInit();
+    private static native int nativeAddPrerender(
+            int nativeExternalPrerenderRequestHandler, Profile profile,
+            String url, String referrer, int width, int height);
+    private static native boolean nativeHasPrerenderedUrl(
+            Profile profile, String url, int webContentsPtr);
+    private static native void nativeCancelCurrentPrerender(
+            int nativeExternalPrerenderRequestHandler);
+}