Cleanup <include/> and etc. in keyboard XML

* Remove keyXPos and keyWidth from key_*.xml and make it more generic.
* Add keyXPos and keyWidth to <include/> generalized key_*.xml.
* Remove zero width <Spacer/> and fold into successive <include/>.

Change-Id: I4b5c02a165ba0bc9ef8741be0b4938c1efaf5e27
diff --git a/java/res/xml-sw600dp/row_symbols4.xml b/java/res/xml-sw600dp/row_symbols4.xml
index 9b6daab..d294e20 100644
--- a/java/res/xml-sw600dp/row_symbols4.xml
+++ b/java/res/xml-sw600dp/row_symbols4.xml
@@ -32,16 +32,16 @@
         <Key
             latin:keyLabel="\@" />
         <include
+            latin:keyXPos="30.750%p"
             latin:keyboardLayout="@xml/key_space" />
         <Key
             latin:keyLabel="&quot;"
             latin:moreKeys="!text/more_keys_for_tablet_double_quote" />
         <Key
             latin:keyLabel="_" />
-        <Spacer
-            latin:keyXPos="-10.00%p"
-            latin:keyWidth="0%p" />
         <include
+            latin:keyXPos="-10.0%p"
+            latin:keyWidth="fillRight"
             latin:keyboardLayout="@xml/key_shortcut" />
     </Row>
 </merge>