Update Pin widget dialog UI according to mocks.

Test: Tested manually and RequestPinItemTest passed
Bug: 182982143
Bug: 182994819
Bug: 182929673
Change-Id: I905ea0c1860d28ee9fbb456ddf6abd728b65bac4
diff --git a/res/values/dimens.xml b/res/values/dimens.xml
index 9d6c936..af4421a 100644
--- a/res/values/dimens.xml
+++ b/res/values/dimens.xml
@@ -138,6 +138,12 @@
     <dimen name="shortcut_preview_padding_right">0dp</dimen>
     <dimen name="shortcut_preview_padding_top">0dp</dimen>
 
+<!-- Pin widget dialog -->
+    <dimen name="pin_widget_button_padding_horizontal">8dp</dimen>
+    <dimen name="pin_widget_button_padding_vertical">4dp</dimen>
+    <dimen name="pin_widget_button_inset_horizontal">4dp</dimen>
+    <dimen name="pin_widget_button_inset_vertical">6dp</dimen>
+
 <!-- Dragging -->
     <!-- Drag padding to add to the bottom of drop targets -->
     <dimen name="drop_target_drag_padding">14dp</dimen>