android: move ResourcePrefetchPredictor usage to LoadingPredictor.

chrome/android/java/src/org/chromium/chrome/browser/customtabs/LoadingPredictor.java

Index: chrome/android/java/src/org/chromium/chrome/browser/customtabs/LoadingPredictor.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/customtabs/LoadingPredictor.java b/chrome/android/java/src/org/chromium/chrome/browser/customtabs/LoadingPredictor.java
new file mode 100644
index 0000000000000000000000000000000000000000..24406dfb35636c6cf3c03b868909592d314a1042
--- /dev/null
+++ b/chrome/android/java/src/org/chromium/chrome/browser/customtabs/LoadingPredictor.java
@@ -0,0 +1,66 @@
+// Copyright 2017 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.customtabs;
+
+import org.chromium.base.ThreadUtils;
+import org.chromium.base.annotations.JNINamespace;
+import org.chromium.chrome.browser.profiles.Profile;
+
+/**
+ * Interface to the loading predictor.
+ *
+ * Allows chrome to hint at a likely future navigation.
+ */
+@JNINamespace("predictors")
+class LoadingPredictor {
+    private static boolean sInitializationStarted;
+
+    private final Profile mProfile;
+
+    /**
+     * @param profile The profile used to get the loading predictor.
+     */
+    public LoadingPredictor(Profile profile) {
+        mProfile = profile;
+    }
+
+    /**
+     * Starts the asynchronous initialization of the loading predictor.
+     */
+    public boolean startInitialization() {
+        ThreadUtils.assertOnUiThread();
+        sInitializationStarted = true;
+        return nativeStartInitialization(mProfile);
+    }
+
+    /**
+     * Hints at a future navigation to a URL.
+     *
+     * @param url The URL to start the prefetch for.

[alexilin, 2017/05/15 13:05:50]

nit: 
Update url parameter description?

[Benoit L, 2017/05/15 13:33:23]

Done.

+     * @return false in case the LoadingPredictor is not usable.
+     */
+    public boolean prepareForPageLoad(String url) {
+        ThreadUtils.assertOnUiThread();
+        if (!sInitializationStarted) {
+            throw new RuntimeException("startInitialization() not called.");
+        }
+        return nativePrepareForPageLoad(mProfile, url);
+    }
+
+    /**
+     * Indicates that a page load hint is no longer active.
+     *
+     * @param url The hinted URL.
+     * @return false in case the LoadingPredictor is not usable.
+     */
+    public boolean cancelPageLoadHint(String url) {
+        ThreadUtils.assertOnUiThread();
+        return nativeCancelPageLoadHint(mProfile, url);
+    }
+
+    private static native boolean nativeStartInitialization(Profile profile);
+    private static native boolean nativePrepareForPageLoad(Profile profile, String url);
+    private static native boolean nativeCancelPageLoadHint(Profile profile, String url);
+}