Add options.omitErrorMessage for should.throw()

This suppresses unnecessary error message (due to the local hardware
configuration) from the exception from should.throw().

BUG=709167
TEST=webaudio/dom-exceptions.html

Review-Url: https://codereview.chromium.org/2803913003
Cr-Commit-Position: refs/heads/master@{#462680}

third_party/WebKit/LayoutTests/webaudio/dom-exceptions-expected.txt

@@ -96,7 +96,7 @@ PASS   node.channelCountMode = "fancy" did not throw an exception.
 PASS   node.channelCountMode is equal to max. 
 PASS   node.channelInterpretation = mode did not throw an exception. 
 PASS   node.channelInterpretation is equal to speakers. 
-PASS   context.destination.channelCount = 99 threw IndexSizeError: "Failed to set the 'channelCount' property on 'AudioNode': The channel count provided (99) is outside the range [1, 2].". 
+PASS   context.destination.channelCount = 99 threw IndexSizeError: [error message omitted]. 
 PASS < [channel-stuff] All assertions passed. (total 7 assertions) 
 PASS > [audioparam]  
 PASS   param.setValueCurveAtTime(null, 0, 0) threw TypeError: "Failed to execute 'setValueCurveAtTime' on 'AudioParam': parameter 1 is not of type 'Float32Array'.". 

third_party/WebKit/LayoutTests/webaudio/dom-exceptions.html

@@ -323,7 +323,7 @@ audit.define(
       should(
           () => context.destination.channelCount = 99,
           'context.destination.channelCount = 99')
-          .throw('IndexSizeError');
+          .throw('IndexSizeError', { omitErrorMessage: true });
 
       task.done();
     });

third_party/WebKit/LayoutTests/webaudio/resources/audit.js

@@ -269,10 +269,15 @@ window.Audit = (function () {
      *   should(() => { let a = b; }, 'A bad code').throw();
      *   should(() => { let c = d; }, 'Assigning d to c.')
      *       .throw('ReferenceError');
+     *   should(() => { let e = f; }, 'Assigning e to f.')
+     *       .throw('ReferenceError', { omitErrorMessage: true });
      *
      * @result
-     *   "PASS   A bad code threw an exception of ReferenceError."
-     *   "PASS   Assigning d to c threw ReferenceError."
+     *   "PASS   A bad code threw an exception of ReferenceError: b is not
+     *       defined."
+     *   "PASS   Assigning d to c threw ReferenceError: d is not defined."
+     *   "PASS   Assigning e to f threw ReferenceError: [error message
+     *       omitted]."
      */
     throw () {
       this._processArguments(arguments);
@@ -287,16 +292,17 @@ window.Audit = (function () {
         // Catch did not happen, so the test is failed.
         failDetail = '${actual} did not throw an exception.';
       } catch (error) {
+        let errorMessage = this._options.omitErrorMessage
+            ? ': [error message omitted]'
+            : ': "' + error.message + '"';
         if (this._expected === null || this._expected === undefined) {
           // The expected error type was not given.
           didThrowCorrectly = true;
-          passDetail = '${actual} threw ' + error.name + ': "'
-              + error.message + '".';
+          passDetail = '${actual} threw ' + error.name + errorMessage + '.';
         } else if (error.name === this._expected) {
           // The expected error type match the actual one.
           didThrowCorrectly = true;
-          passDetail = '${actual} threw ${expected}: "'
-              + error.message + '".';
+          passDetail = '${actual} threw ${expected}' + errorMessage + '.';
         } else {
           didThrowCorrectly = false;
           failDetail = '${actual} threw "' + error.name