Fix failure handling in mock4js to throw instead of calling an undefined function.

chrome/third_party/mock4js/mock4js.js

 /**
  * Mock4JS 0.2
  * http://mock4js.sourceforge.net/
  */
 
 Mock4JS = {
         _mocksToVerify: [],
         _convertToConstraint: function(constraintOrValue) {
                 if(constraintOrValue.argumentMatches) {
                         return constraintOrValue; // it's already an ArgumentMatcher
@@ skipping 104 matching lines @@
         toString: function() {
                 return this.message;
         }
 }
 
 /**
  * Assert function that makes use of the constraint methods
  */ 
 assertThat = function(expected, argumentMatcher) {
         if(!argumentMatcher.argumentMatches(expected)) {
-                fail("Expected '"+expected+"' to be "+argumentMatcher.describe());
+                throw new Mock4JSException("Expected '"+expected+"' to be "+argumentMatcher.describe());
         }
 }
 
 /**
  * CallCounter
  */
 function CallCounter(expectedCount) {
         this._expectedCallCount = expectedCount;
         this._actualCallCount = 0;
 }
@@ skipping 479 matching lines @@
         },
         
         _describeMockSetup: function() {
                 var msg = "\nAllowed:";
                 for(var i=0; i<this._expectedInvocations.length; i++) {
                         var expectedInvocation = this._expectedInvocations[i];
                         msg += "\n" + expectedInvocation.describe();
                 }
                 return msg;
         }
-}
+}