Refactoring all apps search to support external search bar.

- Adding support for an external search bar that can be used
  to search a container view.  This adds a new interface
  AllAppsSearchController which manages the external search
  bar.  Each controller will have its own search implementation
  which means that we no longer need a common AppSearchManager
  interface.
- Removing elevation controller as we no longer have a builtin
  search bar in all apps
- Refactoring container view insets so that they behave
  the same in all containers.
- Refactoring apps view to ensure that we only update the number
  of columns with the available width
- Cleaning up LauncherCallbacks interface

Bug: 20127840
Bug: 21494973

Change-Id: I710b8e18196961d77d8a29f0c345531d480936fe

src/com/android/launcher3/allapps/AllAppsSearchBarController.java

@@ -0,0 +1,97 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.android.launcher3.allapps;
+
+import android.content.ComponentName;
+import android.graphics.Rect;
+import android.view.View;
+import android.view.ViewGroup;
+
+import java.util.ArrayList;
+
+/**
+ * An interface to a search box that AllApps can command.
+ */
+public abstract class AllAppsSearchBarController {
+
+    protected AlphabeticalAppsList mApps;
+    protected Callbacks mCb;
+
+    /**
+     * Sets the references to the apps model and the search result callback.
+     */
+    public final void initialize(AlphabeticalAppsList apps, Callbacks cb) {
+        mApps = apps;
+        mCb = cb;
+        onInitialize();
+    }
+
+    /**
+     * To be overridden by subclasses.  This method will get called when the controller is set,
+     * before getView().
+     */
+    protected abstract void onInitialize();
+
+    /**
+     * Returns the search bar view.
+     * @param parent the parent to attach the search bar view to.
+     */
+    public abstract View getView(ViewGroup parent);
+
+    /**
+     * Focuses the search field to handle key events.
+     */
+    public abstract void focusSearchField();
+
+    /**
+     * Returns whether the search field is focused.
+     */
+    public abstract boolean isSearchFieldFocused();
+
+    /**
+     * Resets the search bar state.
+     */
+    public abstract void reset();
+
+    /**
+     * Returns whether the prediction bar should currently be visible depending on the state of
+     * the search bar.
+     */
+    public abstract boolean shouldShowPredictionBar();
+
+    /**
+     * Callback for getting search results.
+     */
+    public interface Callbacks {
+
+        /**
+         * Called when the bounds of the search bar has changed.
+         */
+        void onBoundsChanged(Rect newBounds);
+
+        /**
+         * Called when the search is complete.
+         *
+         * @param apps sorted list of matching components or null if in case of failure.
+         */
+        void onSearchResult(String query, ArrayList<ComponentName> apps);
+
+        /**
+         * Called when the search results should be cleared.
+         */
+        void clearSearchResult();
+    }
+}