Revert of Cross-repo recipe package system.

scripts/slave/recipe_modules/file/test_api.py

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import os
 
 from recipe_engine import recipe_test_api
 
 
 # We want to be able to really read a file during a recipe test. Of course,
@@ skipping 13 matching lines @@
   '..',
   '..',
   '..',
   '..',
   '..',
 ))
 BUILD = os.path.join(_ROOT, 'build')
 BUILD_INTERNAL = os.path.join(_ROOT, 'build_internal')
 
 class FileTestApi(recipe_test_api.RecipeTestApi):
+  def read_in_build(self, relpath):
+    """Read a file in chrome/trunk/tools/build.
+
+    Args:
+      relpath: A path inside chrome/trunk/tools/build.
+    """
+    # Prevent a user from using .. to escape the build repository.
+    assert '..' not in os.sep.split(relpath), (
+      'You can\'t use .. in read_in_build.'
+    )
+    with open(os.path.join(BUILD, relpath)) as f:
+      return f.read()
+
+  def read_in_build_internal(self, relpath): # pragma: no cover
+    """Read a file in chrome-internal/trunk/tools/build.
+
+    Args:
+      relpath: A path inside chrome-internal/trunk/tools/build.
+    """
+    # Prevent a user from using .. to escape the build_internal repository.
+    assert '..' not in os.sep.split(relpath), (
+      'You can\'t use .. in read_in_build.'
+    )
+    with open(os.path.join(BUILD_INTERNAL, relpath)) as f:
+      return f.read()
+
   def listdir(self, files):
     def listdir_callback():
       return self.m.json.output(files)
     return listdir_callback