--- a/testing/web-platform/tests/media-source/mediasource-addsourcebuffer.html
+++ b/testing/web-platform/tests/media-source/mediasource-addsourcebuffer.html
@@ -15,17 +15,17 @@
               assert_throws("InvalidStateError",
                           function() { mediaSource.addSourceBuffer(MediaSourceUtil.AUDIO_VIDEO_TYPE); },
                           "addSourceBuffer() threw an exception when in 'ended' state.");
               test.done();
           }, "Test addSourceBuffer() in 'ended' state.");
 
           mediasource_test(function(test, mediaElement, mediaSource)
           {
-              assert_throws("InvalidAccessError",
+              assert_throws(new TypeError(),
                           function() { mediaSource.addSourceBuffer(""); },
                           "addSourceBuffer() threw an exception when passed an empty string.");
               test.done();
           }, "Test addSourceBuffer() with empty type");
 
           mediasource_test(function(test, mediaElement, mediaSource)
           {
               assert_throws("NotSupportedError",

--- a/testing/web-platform/tests/media-source/mediasource-appendwindow.html
+++ b/testing/web-platform/tests/media-source/mediasource-appendwindow.html
@@ -39,45 +39,45 @@
               assert_throws(new TypeError(),
                   function() { sourceBuffer.appendWindowStart = Number.POSITIVE_INFINITY; },
                   "set appendWindowStart throws an exception for Number.POSITIVE_INFINITY.");
 
               assert_throws(new TypeError(),
                   function() { sourceBuffer.appendWindowStart = Number.NaN; },
                   "set appendWindowStart throws an exception for Number.NaN.");
 
-              assert_throws("InvalidAccessError",
+              assert_throws(new TypeError(),
                   function() { sourceBuffer.appendWindowStart = 600.0; },
                   "set appendWindowStart throws an exception when greater than appendWindowEnd.");
 
-              assert_throws("InvalidAccessError",
+              assert_throws(new TypeError(),
                   function() { sourceBuffer.appendWindowStart = sourceBuffer.appendWindowEnd; },
                   "set appendWindowStart throws an exception when equal to appendWindowEnd.");
 
-              assert_throws("InvalidAccessError",
+              assert_throws(new TypeError(),
                   function() { sourceBuffer.appendWindowEnd = sourceBuffer.appendWindowStart; },
                   "set appendWindowEnd throws an exception when equal to appendWindowStart.");
 
-              assert_throws("InvalidAccessError",
+              assert_throws(new TypeError(),
                   function() { sourceBuffer.appendWindowEnd = sourceBuffer.appendWindowStart - 1; },
                   "set appendWindowEnd throws an exception if less than appendWindowStart.");
 
-              assert_throws("InvalidAccessError",
+              assert_throws(new TypeError(),
                   function() { sourceBuffer.appendWindowStart = -100.0; },
                   "set appendWindowStart throws an exception when less than 0.");
 
-              assert_throws("InvalidAccessError",
+              assert_throws(new TypeError(),
                   function() { sourceBuffer.appendWindowEnd = -100.0; },
                   "set appendWindowEnd throws an exception when less than 0.");
 
-              assert_throws("InvalidAccessError",
+              assert_throws(new TypeError(),
                   function() { sourceBuffer.appendWindowEnd = Number.NaN; },
                   "set appendWindowEnd throws an exception if NaN.");
 
-              assert_throws("InvalidAccessError",
+              assert_throws(new TypeError(),
                   function() { sourceBuffer.appendWindowEnd = undefined; },
                   "set appendWindowEnd throws an exception if undefined.");
 
               assert_throws({name: "TypeError"},
                   function() { sourceBuffer.appendWindowStart = undefined; },
                   "set appendWindowStart throws an exception if undefined.");
 
               test.done();

--- a/testing/web-platform/tests/media-source/mediasource-duration-boundaryconditions.html
+++ b/testing/web-platform/tests/media-source/mediasource-duration-boundaryconditions.html
@@ -44,19 +44,19 @@
               }, description);
           }
 
           DurationBoundaryConditionTest(Math.pow(2, 31) - 1, null, "Set duration to 2^31 - 1");
           DurationBoundaryConditionTest(1, null, "Set duration to 1");
           DurationBoundaryConditionTest(Number.MAX_VALUE, null, "Set duration to Number.MAX_VALUE");
           DurationBoundaryConditionTest(Number.MIN_VALUE, null, "Set duration to Number.MIN_VALUE");
           DurationBoundaryConditionTest(Number.MAX_VALUE - 1, null, "Set duration to Number.MAX_VALUE - 1");
-          DurationBoundaryConditionTest(Number.MIN_VALUE - 1, "InvalidAccessError", "Set duration to Number.MIN_VALUE - 1");
+          DurationBoundaryConditionTest(Number.MIN_VALUE - 1, new TypeError(), "Set duration to Number.MIN_VALUE - 1");
           DurationBoundaryConditionTest(Number.POSITIVE_INFINITY, null, "Set duration to Number.POSITIVE_INFINITY");
-          DurationBoundaryConditionTest(Number.NEGATIVE_INFINITY, "InvalidAccessError", "Set duration to Number.NEGATIVE_INFINITY");
-          DurationBoundaryConditionTest(-1 * Number.MAX_VALUE, "InvalidAccessError", "Set duration to lowest value.");
-          DurationBoundaryConditionTest(-101.9, "InvalidAccessError", "Set duration to a negative double.");
+          DurationBoundaryConditionTest(Number.NEGATIVE_INFINITY, new TypeError(), "Set duration to Number.NEGATIVE_INFINITY");
+          DurationBoundaryConditionTest(-1 * Number.MAX_VALUE, new TypeError(), "Set duration to lowest value.");
+          DurationBoundaryConditionTest(-101.9, new TypeError(), "Set duration to a negative double.");
           DurationBoundaryConditionTest(101.9, null, "Set duration to a positive double.");
           DurationBoundaryConditionTest(0, null, "Set duration to zero");
-          DurationBoundaryConditionTest(NaN, "InvalidAccessError", "Set duration to NaN");
+          DurationBoundaryConditionTest(NaN, new TypeError(), "Set duration to NaN");
         </script>
     </body>
 </html>

--- a/testing/web-platform/tests/media-source/mediasource-remove.html
+++ b/testing/web-platform/tests/media-source/mediasource-remove.html
@@ -8,17 +8,17 @@
     </head>
     <body>
         <div id="log"></div>
         <script>
           mediasource_test(function(test, mediaElement, mediaSource)
           {
               var sourceBuffer = mediaSource.addSourceBuffer(MediaSourceUtil.AUDIO_VIDEO_TYPE);
 
-              assert_throws("InvalidAccessError", function()
+              assert_throws(new TypeError(), function()
               {
                   sourceBuffer.remove(-1, 2);
               }, "remove");
 
               test.done();
           }, "Test remove with an negative start.");
 
           mediasource_test(function(test, mediaElement, mediaSource)
@@ -37,55 +37,55 @@
           }, "Test remove with non-finite start.");
 
           mediasource_test(function(test, mediaElement, mediaSource)
           {
               var sourceBuffer = mediaSource.addSourceBuffer(MediaSourceUtil.AUDIO_VIDEO_TYPE);
 
               mediaSource.duration = 10;
 
-              assert_throws("InvalidAccessError", function()
+              assert_throws(new TypeError(), function()
               {
                   sourceBuffer.remove(11, 12);
               }, "remove");
 
               test.done();
           }, "Test remove with a start beyond the duration.");
 
           mediasource_test(function(test, mediaElement, mediaSource)
           {
               var sourceBuffer = mediaSource.addSourceBuffer(MediaSourceUtil.AUDIO_VIDEO_TYPE);
 
               mediaSource.duration = 10;
 
-              assert_throws("InvalidAccessError", function()
+              assert_throws(new TypeError(), function()
               {
                   sourceBuffer.remove(2, 1);
               }, "remove");
 
               test.done();
           }, "Test remove with a start larger than the end.");
 
           mediasource_test(function(test, mediaElement, mediaSource)
           {
               var sourceBuffer = mediaSource.addSourceBuffer(MediaSourceUtil.AUDIO_VIDEO_TYPE);
 
-              assert_throws("InvalidAccessError", function()
+              assert_throws(new TypeError(), function()
               {
                   sourceBuffer.remove(0, Number.NEGATIVE_INFINITY);
               }, "remove");
 
               test.done();
           }, "Test remove with a NEGATIVE_INFINITY end.");
 
           mediasource_test(function(test, mediaElement, mediaSource)
           {
               var sourceBuffer = mediaSource.addSourceBuffer(MediaSourceUtil.AUDIO_VIDEO_TYPE);
 
-              assert_throws("InvalidAccessError", function()
+              assert_throws(new TypeError(), function()
               {
                   sourceBuffer.remove(0, Number.NaN);
               }, "remove");
 
               test.done();
           }, "Test remove with a NaN end.");
 
           mediasource_test(function(test, mediaElement, mediaSource)