Add condition attribute for MIME media types from Content-Type header.

chrome/test/data/extensions/api_test/webrequest/test_declarative.js

Index: chrome/test/data/extensions/api_test/webrequest/test_declarative.js
diff --git a/chrome/test/data/extensions/api_test/webrequest/test_declarative.js b/chrome/test/data/extensions/api_test/webrequest/test_declarative.js
index dd1474bf552f934d80b3140ba039bd6fff0ef978..446dc33e90b757c6dc9d0590dd22f055f7bae695 100644
--- a/chrome/test/data/extensions/api_test/webrequest/test_declarative.js
+++ b/chrome/test/data/extensions/api_test/webrequest/test_declarative.js
@@ -45,6 +45,11 @@ function getURLHttpRedirectTest() {
       "files/extensions/api_test/webrequest/declarative/a.html");
 }
 
+function getURLHttpWithHeaders() {
+  return getServerURL(
+      "files/extensions/api_test/webrequest/declarative/headers.html");
+}
+
 function getURLSetCookie() {
   return getServerURL('set-cookie?Foo=Bar');
 }
@@ -67,7 +72,7 @@ runTests([
         { label: "onErrorOccurred",
           event: "onErrorOccurred",
           details: {
-            url: getURLHttpSimple(),
+            url: getURLHttpWithHeaders(),
             fromCache: false,
             error: "net::ERR_BLOCKED_BY_CLIENT"
           }
@@ -82,10 +87,11 @@ runTests([
                  'ports': [testServerPort, [1000, 2000]],
                  'schemes': ["http"]
              },
-             'resourceType': ["main_frame"]})],
+             'resourceType': ["main_frame"],
+             'contentType': ["text/html"]})],
          'actions': [new CancelRequest()]}
       ],
-      function() {navigateAndWait(getURLHttpSimple());}
+      function() {navigateAndWait(getURLHttpWithHeaders());}
     );
   },