Fixing CssStyleDeclaration to not throw exceptions for unsupported values.

tools/dom/templates/html/impl/impl_CSSStyleDeclaration.darttemplate

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of $LIBRARYNAME;
 
 String _cachedBrowserPrefix;
 
 String get _browserPrefix {
   if (_cachedBrowserPrefix == null) {
@@ skipping 35 matching lines @@
 
 $!MEMBERS
 
   String getPropertyValue(String propertyName) {
     var propValue = _getPropertyValue(propertyName);
     return propValue != null ? propValue : '';
   }
 
 $if DART2JS
   void setProperty(String propertyName, String value, [String priority]) {
-    JS('void', '#.setProperty(#, #, #)', this, propertyName, value, priority);
-    // Bug #2772, IE9 requires a poke to actually apply the value.
-    if (JS('bool', '!!#.setAttribute', this)) {
-      JS('void', '#.setAttribute(#, #)', this, propertyName, value);
-    }
+    // try/catch for IE9 which throws on unsupported values.
+    try {
+      JS('void', '#.setProperty(#, #, #)', this, propertyName, value, priority);
+      // Bug #2772, IE9 requires a poke to actually apply the value.
+      if (JS('bool', '!!#.setAttribute', this)) {
+        JS('void', '#.setAttribute(#, #)', this, propertyName, value);
+      }
+    } catch (e) {}
   }
 
   /**
    * Checks to see if CSS Transitions are supported.
    */
   static bool get supportsTransitions {
     if (JS('bool', '"transition" in document.body.style')) {
       return true;
     }
     var propertyName = '${_browserPropertyPrefix}Transition';
@@ skipping 3158 matching lines @@
 
   /** Gets the value of "zoom" */
   String get zoom =>
     getPropertyValue('zoom');
 
   /** Sets the value of "zoom" */
   void set zoom(String value) {
     setProperty('zoom', value, '');
   }
 }