Replace stretched background textures with real gradients

Change-Id: I320733aaef191318d32fa823d9a6140585f49417

Author: Romain Guy

core/res/res/drawable-nodpi/background_holo_dark.png

@@ -0,0 +1,22 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2012 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.
+-->
+
+<shape xmlns:android="http://schemas.android.com/apk/res/android">
+    <gradient
+            android:startColor="#ff000000"
+            android:endColor="#ff272d33"
+            android:angle="270" />
+</shape>

core/res/res/drawable-nodpi/background_holo_light.png

@@ -0,0 +1,22 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2012 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.
+-->
+
+<shape xmlns:android="http://schemas.android.com/apk/res/android">
+    <gradient
+            android:startColor="#ffe8e8e8"
+            android:endColor="#fff3f3f3"
+            android:angle="270" />
+</shape>