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..768f09ef77b526382d99b449f560037766592835
--- /dev/null
+++ b/chrome/android/java/src/org/chromium/chrome/browser/tabmodel/TabModelJniBridge.java
@@ -0,0 +1,103 @@
+// 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() {

[David Trainor- moved to gerrit, 2014/10/09 20:43:42]

Maybe add a comment here about how this will invalidate all other native
references to this object in child classes.

[gone, 2014/10/10 22:39:19]

Done.

+        if (mNativeTabModelJniBridge != 0) {
+            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
+    protected void setIndex(int index) {

[David Trainor- moved to gerrit, 2014/10/09 20:43:42]

Can this be private?

[gone, 2014/10/10 22:39:19]

This is called by TabModelBase.cancelTabClosure, so not currently.

+        TabModelUtils.setIndex(this, 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);
+
+    @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);
+}