Break apart the TabModelBase's JNI calls into its own class

chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModelJniBridge.java

Index: chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModelJniBridge.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModelJniBridge.java b/chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModelJniBridge.java
new file mode 100644
index 0000000000000000000000000000000000000000..b74d6bac18bdc6047eff71043e909d7cb4f5dbc7
--- /dev/null
+++ b/chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModelJniBridge.java
@@ -0,0 +1,123 @@
+// Copyright 2014 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.tabmodel;
+
+import org.chromium.base.CalledByNative;
+import org.chromium.chrome.browser.Tab;
+import org.chromium.chrome.browser.profiles.Profile;
+
+/**
+ * Bridges between the C++ and Java {@link TabModel} interfaces.
+ */
+public abstract class TabModelJniBridge implements TabModel {
+    private final boolean mIsIncognito;
+
+    /** Native TabModelJniBridge pointer, which will be set by {@link #setNativePtr(long)}. */
+    private long mNativeTabModelJniBridge;
+
+    public TabModelJniBridge(boolean isIncognito) {
+        mIsIncognito = isIncognito;
+    }
+
+    @CalledByNative
+    private void clearNativePtr() {
+        assert mNativeTabModelJniBridge != 0;
+        mNativeTabModelJniBridge = 0;
+    }
+
+    @CalledByNative
+    private void setNativePtr(long nativePointer) {
+        assert mNativeTabModelJniBridge == 0;
+        mNativeTabModelJniBridge = nativePointer;
+    }
+
+    @Override
+    public void destroy() {
+        if (mNativeTabModelJniBridge != 0) {
+            // This will invalidate all other native references to this object in child classes.
+            nativeDestroy(mNativeTabModelJniBridge);
+            mNativeTabModelJniBridge = 0;
+        }
+    }
+
+    @Override
+    public boolean isIncognito() {
+        return mIsIncognito;
+    }
+
+    @Override
+    public Profile getProfile() {
+        return nativeGetProfileAndroid(mNativeTabModelJniBridge);
+    }
+
+    /** Broadcast a native-side notification that all tabs are now loaded from storage. */
+    public void broadcastSessionRestoreComplete() {
+        assert mNativeTabModelJniBridge != 0;
+        nativeBroadcastSessionRestoreComplete(mNativeTabModelJniBridge);
+    }
+
+    /**
+     * Called by subclasses when a Tab is added to the TabModel.
+     * @param tab Tab being added to the model.
+     */
+    protected void tabAddedToModel(Tab tab) {
+        if (mNativeTabModelJniBridge != 0) nativeTabAddedToModel(mNativeTabModelJniBridge, tab);
+    }
+
+    /**
+     * Sets the TabModel's index.
+     * @param index Index of the Tab to select.
+     */
+    @CalledByNative
+    private void setIndex(int index) {
+        TabModelUtils.setIndex(this, index);
+    }
+
+    @Override
+    @CalledByNative
+    public abstract Tab getTabAt(int index);
+
+    /**
+     * Closes the Tab at a particular index.
+     * @param index Index of the tab to close.
+     * @return Whether the was successfully closed.
+     */
+    @CalledByNative
+    protected abstract boolean closeTabAt(int index);
+
+    /**
+     * Creates a Tab with the given WebContents.
+     * @param incognito Whether or not the tab is incognito.
+     * @param nativeWebContents Pointer to the native WebContents.
+     * @param parentId ID of the parent.
+     */
+    @CalledByNative
+    protected abstract Tab createTabWithNativeContents(
+            boolean incognito, long nativeWebContents, int parentId);
+
+    /**
+     * Creates a Tab with the given WebContents for DevTools.
+     * @param url URL to show.
+     */
+    @CalledByNative
+    protected abstract Tab createNewTabForDevTools(String url);
+
+    @Override
+    @CalledByNative
+    public abstract int getCount();
+
+    @Override
+    @CalledByNative
+    public abstract int index();
+
+    /** @return Whether or not a sync session is currently being restored. */
+    @CalledByNative
+    protected abstract boolean isSessionRestoreInProgress();
+
+    private native Profile nativeGetProfileAndroid(long nativeTabModelJniBridge);
+    private native void nativeBroadcastSessionRestoreComplete(long nativeTabModelJniBridge);
+    private native void nativeDestroy(long nativeTabModelJniBridge);
+    private native void nativeTabAddedToModel(long nativeTabModelJniBridge, Tab tab);
+}