Adding an overridable DrawableFactory to allow creating custom icon drawables

> Adding ItemInfo as a parameter for creating drawable

Change-Id: I793acb0381d2b8df4db0a08317dddf1464788ebc

src/com/android/launcher3/graphics/DrawableFactory.java

@@ -0,0 +1,69 @@
+/*
+ * Copyright (C) 2016 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.graphics;
+
+import android.content.Context;
+import android.graphics.Bitmap;
+import android.text.TextUtils;
+
+import com.android.launcher3.FastBitmapDrawable;
+import com.android.launcher3.ItemInfo;
+import com.android.launcher3.R;
+
+import java.lang.reflect.InvocationTargetException;
+
+/**
+ * Factory for creating new drawables.
+ */
+public class DrawableFactory {
+
+    private static DrawableFactory sInstance;
+    private static final Object LOCK = new Object();
+
+    public static DrawableFactory get(Context context) {
+        synchronized (LOCK) {
+            if (sInstance == null) {
+                context = context.getApplicationContext();
+                sInstance = loadByName(context.getString(R.string.drawable_factory_class), context);
+            }
+            return sInstance;
+        }
+    }
+
+    public static DrawableFactory loadByName(String className, Context context) {
+        if (!TextUtils.isEmpty(className)) {
+            try {
+                Class<?> cls = Class.forName(className);
+                return (DrawableFactory)
+                        cls.getDeclaredConstructor(Context.class).newInstance(context);
+            } catch (ClassNotFoundException | InstantiationException | IllegalAccessException
+                    | ClassCastException | NoSuchMethodException | InvocationTargetException e) {
+                return new DrawableFactory();
+            }
+        }
+        return new DrawableFactory();
+    }
+
+    /**
+     * Returns a FastBitmapDrawable with the icon.
+     */
+    public FastBitmapDrawable newIcon(Bitmap icon, ItemInfo info) {
+        FastBitmapDrawable d = new FastBitmapDrawable(icon);
+        d.setFilterBitmap(true);
+        return d;
+    }
+}