New text field to display the punched numbers.

The numbers are centered in the field.
The active background is used when non empty.
Added top and bottom margin.
The font used appear a bit small compare to the
design, need to come up with a textAppearance resource
to control it (future CL)

Tested on cdma and gsm phones.

Bug: 2104523
diff --git a/src/com/android/contacts/TwelveKeyDialer.java b/src/com/android/contacts/TwelveKeyDialer.java
index ebb76c0..bdc6b6f 100644
--- a/src/com/android/contacts/TwelveKeyDialer.java
+++ b/src/com/android/contacts/TwelveKeyDialer.java
@@ -155,6 +155,13 @@
             mDigits.getText().clear();
         }
 
+        final boolean notEmpty = mDigits.length() != 0;
+        if (notEmpty) {
+            mDigits.setBackgroundDrawable(mDigitsBackground);
+        } else {
+            mDigits.setBackgroundDrawable(mDigitsEmptyBackground);
+        }
+
         updateDialAndDeleteButtonStateEnabledAttr();
     }
 
@@ -165,10 +172,9 @@
         // Set the content view
         setContentView(getContentViewResource());
 
-        // Load up the resources for the text field and delete button
+        // Load up the resources for the text field.
         Resources r = getResources();
         mDigitsBackground = r.getDrawable(R.drawable.btn_dial_textfield_active);
-        //mDigitsBackground.setDither(true);
         mDigitsEmptyBackground = r.getDrawable(R.drawable.btn_dial_textfield);
 
         mDigits = (EditText) findViewById(R.id.digits);