Update app widget resize frame UI.

Mock: https://docs.google.com/presentation/d/1UxdDh8EFhPbdRWRwzjbpgL-j02ew4Ew3eG3XBCeoYdo/edit#slide=id.8YyBaHq
Implementation: https://screenshot.googleplex.com/BEFwWBmXXx8xXdS

I will update the drag handles in a follow-up CL since their specs
aren't ready yet.

Test: manual
Bug: 181774580
Change-Id: I19a99e6dbe106754da0fac56a5c2e7eb9eb90cef

res/drawable/widget_resize_frame.xml

@@ -0,0 +1,22 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+     Copyright (C) 2021 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"
+    android:shape="rectangle">
+    <solid android:color="@android:color/transparent" />
+    <corners android:radius="@android:dimen/system_app_widget_background_radius" />
+    <stroke android:width="2dp" android:color="?android:attr/colorAccent" />
+</shape>

res/layout/app_widget_resize_frame.xml

@@ -18,15 +18,20 @@
     xmlns:android="http://schemas.android.com/apk/res/android"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
-    android:background="@drawable/widget_resize_shadow"
-    android:foreground="@drawable/widget_resize_frame"
-    android:foregroundTint="?attr/workspaceTextColor"
     android:padding="0dp">
 
     <FrameLayout
         android:layout_width="match_parent"
         android:layout_height="match_parent" >
 
+        <!-- Frame -->
+        <ImageView
+            android:layout_width="match_parent"
+            android:layout_height="match_parent"
+            android:layout_gravity="center"
+            android:layout_margin="@dimen/resize_frame_margin"
+            android:src="@drawable/widget_resize_frame" />
+
         <!-- Left -->
         <ImageView
             android:layout_width="wrap_content"
@@ -34,7 +39,7 @@
             android:layout_gravity="left|center_vertical"
             android:layout_marginLeft="@dimen/widget_handle_margin"
             android:src="@drawable/ic_widget_resize_handle"
-            android:tint="?attr/workspaceTextColor" />
+            android:tint="?android:attr/colorAccent" />
 
         <!-- Top -->
         <ImageView
@@ -43,7 +48,7 @@
             android:layout_gravity="top|center_horizontal"
             android:layout_marginTop="@dimen/widget_handle_margin"
             android:src="@drawable/ic_widget_resize_handle"
-            android:tint="?attr/workspaceTextColor" />
+            android:tint="?android:attr/colorAccent" />
 
         <!-- Right -->
         <ImageView
@@ -52,7 +57,7 @@
             android:layout_gravity="right|center_vertical"
             android:layout_marginRight="@dimen/widget_handle_margin"
             android:src="@drawable/ic_widget_resize_handle"
-            android:tint="?attr/workspaceTextColor" />
+            android:tint="?android:attr/colorAccent" />
 
         <!-- Bottom -->
         <ImageView
@@ -61,7 +66,7 @@
             android:layout_gravity="bottom|center_horizontal"
             android:layout_marginBottom="@dimen/widget_handle_margin"
             android:src="@drawable/ic_widget_resize_handle"
-            android:tint="?attr/workspaceTextColor" />
+            android:tint="?android:attr/colorAccent" />
 
     </FrameLayout>
 </com.android.launcher3.AppWidgetResizeFrame>

res/values/dimens.xml

@@ -52,6 +52,7 @@
 <!-- App Widget resize frame -->
     <dimen name="widget_handle_margin">13dp</dimen>
     <dimen name="resize_frame_background_padding">24dp</dimen>
+    <dimen name="resize_frame_margin">22dp</dimen>
 
 <!-- Fast scroll -->
     <dimen name="fastscroll_track_min_width">6dp</dimen>