Update the drag to dismiss UI to be closer to design

Rather than a circular target for drag to dismiss, there is text / icon
as well as a gradient. As the PIP approaches the text / icon they grow
in size. If the PIP is released overtop of the text / icon, it is
dismissed.

Test: Using PIP test app, have a PIP, drag it to dismiss target area.
Change-Id: I339ad14e144dfd61f0e990ba4d2559642a47b141
diff --git a/packages/SystemUI/res/values/strings.xml b/packages/SystemUI/res/values/strings.xml
index d3e965a..0e48865 100644
--- a/packages/SystemUI/res/values/strings.xml
+++ b/packages/SystemUI/res/values/strings.xml
@@ -1746,8 +1746,8 @@
     <!-- Label for PIP action to Minimize the PIP [CHAR LIMIT=25] -->
     <string name="pip_phone_minimize">Minimize</string>
 
-    <!-- Label for PIP action to Dismiss the PIP -->
-    <string name="pip_phone_dismiss">Dismiss</string>
+    <!-- Label for PIP the drag to close zone [CHAR LIMIT=NONE]-->
+    <string name="pip_phone_close">Close</string>
 
     <!-- PIP section of the tuner. Non-translatable since it should
         not appear on production builds ever. -->