drive: Use "/drive/root" namespace and fix Files app and tests.

chrome/test/data/extensions/api_test/file_browser/filesystem_operations_test/test.js

Index: chrome/test/data/extensions/api_test/file_browser/filesystem_operations_test/test.js
diff --git a/chrome/test/data/extensions/api_test/file_browser/filesystem_operations_test/test.js b/chrome/test/data/extensions/api_test/file_browser/filesystem_operations_test/test.js
index 3d4dbf3bf4d38f96147591db19a3dedb0317615d..012e05295305548cced06ab90ec9b15491a68f9e 100644
--- a/chrome/test/data/extensions/api_test/file_browser/filesystem_operations_test/test.js
+++ b/chrome/test/data/extensions/api_test/file_browser/filesystem_operations_test/test.js
@@ -14,23 +14,25 @@
  *
  * The test files on file systems should be created before running the test
  * extension. The test extension expects following hierarchy:
- *   mount_point_root - test_dir - - subdir
- *                                |
- *                                 - empty_test_dir
- *                                |
- *                                 - test_file.xul
- *                                |
- *                                 - test_file.xul.foo
- *                                |
- *                                 - test_file.tiff
- *                                |
- *                                 - test_file.tiff.foo
+ *   mount_point_root - (root) - test_dir - - subdir
+ *                                         |
+ *                                          - empty_test_dir
+ *                                         |
+ *                                          - test_file.xul
+ *                                         |
+ *                                          - test_file.xul.foo
+ *                                         |
+ *                                          - test_file.tiff
+ *                                         |
+ *                                          - test_file.tiff.foo
  *
- * mount_point_root/test_dir/subdir/ will be used as destination dir for copy
- * and move operations.
- * mount_point_root/test_dir/empty_test_dir/ should be empty and will stay empty
- * until the end of the test.
- * mount_point_root/test_dir/test_file.xul will not change during the test.
+ * mount_point_root/root exists only for Drive.
+ * mount_point_root/(root/)test_dir/subdir/ will be used as destination dir for
+ * copy and move operations.
+ * mount_point_root/(root/)test_dir/empty_test_dir/ should be empty and will
+ * stay empty until the end of the test.
+ * mount_point_root/(root/)test_dir/test_file.xul will not change during the
+ * test.
  *
  * All files should initially have content: kInitialFileContent.
  */
@@ -60,13 +62,20 @@ function assertEqAndRunCallback(expectedValue, value, errorMessage,
  * as an argument. For Other methods, the callback argument should be ignored.
  */
 
+// Gets the path for operations. The path is relative to the mount point for
+// local entries and relative to the "My Drive" root for Drive entries.
+function getPath(relativePath, isOnDrive) {
+  return (isOnDrive ? 'root/' : '') + relativePath;
+}
+
 // Gets the directory mountPoint/path
 function getDirectory(mountPoint, path, shouldCreate, expectSuccess, callback) {
   var messagePrefix = shouldCreate ? 'Creating ' : 'Getting ';
   var message = messagePrefix + 'directory: \'' + path +'\'.';
+  var isOnDrive = mountPoint.fullPath == '/drive';
 
   mountPoint.getDirectory(
-      path, {create: shouldCreate},
+      getPath(path, isOnDrive), {create: shouldCreate},
       assertEqAndRunCallback.bind(null, expectSuccess, true, message, callback),
       assertEqAndRunCallback.bind(null, expectSuccess, false, message,
                                   callback, null));
@@ -76,9 +85,10 @@ function getDirectory(mountPoint, path, shouldCreate, expectSuccess, callback) {
 function getFile(mountPoint, path, shouldCreate, expectSuccess, callback) {
   var messagePrefix = shouldCreate ? 'Creating ' : 'Getting ';
   var message = messagePrefix + 'file: \'' + path +'\'.';
+  var isOnDrive = mountPoint.fullPath == '/drive';
 
   mountPoint.getFile(
-      path, {create: shouldCreate},
+      getPath(path, isOnDrive), {create: shouldCreate},
       assertEqAndRunCallback.bind(null, expectSuccess, true, message, callback),
       assertEqAndRunCallback.bind(null, expectSuccess, false, message,
                                   callback, null));
@@ -88,7 +98,6 @@ function getFile(mountPoint, path, shouldCreate, expectSuccess, callback) {
 // should always succeed.
 function readFileAndExpectContent(mountPoint, path, expectedContent, callback) {
   var message = 'Content of the file \'' + path + '\'.';
-
   getFile(mountPoint, path, false, true, function(entry) {
     var reader = new FileReader();
     reader.onload = function() {
@@ -147,7 +156,6 @@ function abortWriteFile(mountPoint, path, callback) {
 // Truncates file mountPoint/path to lenght |lenght|.
 function truncateFile(mountPoint, path, length, expectSuccess, callback) {
   var message = 'Truncating file: \'' + path + '\' to length ' + length + '.';
-
   getFile(mountPoint, path, false, true, function(entry) {
     entry.createWriter(function(writer) {
       writer.onwrite = assertEqAndRunCallback.bind(null,