Add floating dialpad action button

* Replace fake action bar at the bottom of the screen with a floating
action button which casts a shadow.

* Remove the now unused mDialpadOverflowMenu button in DialtactsActivity

* Modify dialpad layout to add a bottom row of buttons which provide
access to the add contact button and overflow menu

* Fix dialpad layout so the heights applied in XML are actually
respected - previously they were being ignored and each dialpad key
was being assigned the height of MATCH_PARENT

Bug: 13932988

Change-Id: I6e48c00c5ceeeffed142c3dd259e630d6daf8111
diff --git a/res/layout/dialpad_key.xml b/res/layout/dialpad_key.xml
index 5bf858c..abbe4f9 100644
--- a/res/layout/dialpad_key.xml
+++ b/res/layout/dialpad_key.xml
@@ -17,7 +17,7 @@
 <!-- A layout representing a single key in the dialpad -->
 <com.android.dialer.dialpad.DialpadKeyButton
     xmlns:android="http://schemas.android.com/apk/res/android"
-    style="@style/DialpadKeyButtonStyle">
+    style="@style/DialpadKeyButtonStyle" >
 
     <LinearLayout style="@style/DialpadKeyInternalLayoutStyle">