Add extension API test for FileSystem API.

chrome/test/data/extensions/api_test/fileapi/tab.html

Index: chrome/test/data/extensions/api_test/fileapi/tab.html
diff --git a/chrome/test/data/extensions/api_test/fileapi/tab.html b/chrome/test/data/extensions/api_test/fileapi/tab.html
new file mode 100644
index 0000000000000000000000000000000000000000..8186225f5f1733e9b6f3d36d83158741b3301f9d
--- /dev/null
+++ b/chrome/test/data/extensions/api_test/fileapi/tab.html
@@ -0,0 +1,19 @@
+<script>
+function errorCallback(error) {
+  chrome.test.fail("Got unexpected error: " + error.code);
+}
+
+function successCallback(entry) {
+  chrome.test.succeed();
+}
+
+chrome.test.runTests([function tab() {
+  console.log("Requesting a filesystem...");
+  requestFileSystem(window.TEMPORARY, 100, function(fs) {
+    // See if we get the same filesystem image.
+    console.log("DONE requesting filesystem: " + fs.name);
+    fs.root.getFile('dir/file', {create:false},
+                    successCallback, errorCallback);
+  }, errorCallback);
+}]);
+</script>