feat(httpBackend) Patch for Firefox bug w/ CORS and resonse headers

src/ng/httpBackend.js

@@ -65,11 +65,33 @@ function createHttpBackend($browser, XHR, $browserDefer, callbacks, rawDocument,
       // always async
       xhr.onreadystatechange = function() {
         if (xhr.readyState == 4) {
+          var responseHeaders = xhr.getAllResponseHeaders();
+
+          // begin: workaround to overcome Firefox CORS http response headers bug 
+          // https://bugzilla.mozilla.org/show_bug.cgi?id=608735
+          // Firefox already patched in nightly. Should land in Firefox 21.
+
+          // CORS "simple response headers" http://www.w3.org/TR/cors/
+          var value,
+              simpleHeaders = ["Cache-Control", "Content-Language", "Content-Type",
+                                  "Expires", "Last-Modified", "Pragma"];
+          if (!responseHeaders) {
+            responseHeaders = "";
+            forEach(simpleHeaders, function (header) {
+              var value = xhr.getResponseHeader(header);
+              if (value) {
+                  responseHeaders += header + ": " + value + "\n";
+              }
+            });
+          }
+          // end workaround.              
+
           completeRequest(callback, status || xhr.status, xhr.response || xhr.responseText,
-                          xhr.getAllResponseHeaders());
+                          responseHeaders);
         }
       };
 
+
       if (withCredentials) {
         xhr.withCredentials = true;
       }

test/ng/httpBackendSpec.js

@@ -116,6 +116,9 @@ describe('$httpBackend', function() {
       };
 
       this.getAllResponseHeaders = valueFn('');
+      // for temporary Firefox CORS workaround
+	  // see https://github.com/angular/angular.js/issues/1468
+      this.getResponseHeader = valueFn('');
     }
 
     callback.andCallFake(function(status, response) {