Use relative paths in svndiff, so results can be exported by Apache

tools/svndiff.py

Index: tools/svndiff.py
===================================================================
--- tools/svndiff.py	(revision 11259)
+++ tools/svndiff.py	(working copy)
@@ -220,10 +220,8 @@
     path_to_skdiff = os.path.abspath(FindPathToSkDiff(path_to_skdiff))
     if not dest_dir:
         dest_dir = tempfile.mkdtemp()
-    dest_dir = os.path.abspath(dest_dir)
 
-    os.chdir(source_dir)
-    using_svn = os.path.isdir('.svn')
+    using_svn = os.path.isdir(os.path.join(source_dir, '.svn'))
 
     # Prepare temporary directories.
     modified_flattened_dir = os.path.join(dest_dir, 'modified_flattened')
@@ -236,7 +234,7 @@
     # Get a list of all locally modified (including added/deleted) files,
     # descending subdirectories.
     if using_svn:
-        svn_repo = svn.Svn('.')
+        svn_repo = svn.Svn(source_dir)
         modified_file_paths = svn_repo.GetFilesWithStatus(
             svn.STATUS_ADDED | svn.STATUS_DELETED | svn.STATUS_MODIFIED)
     else:
@@ -259,7 +257,7 @@
             platform_prefix = re.sub(os.sep, '__',
                                      os.path.dirname(modified_file_path)) + '__'
             _CallJsonDiff(old_json_path=original_file_path,
-                          new_json_path=modified_file_path,
+                          new_json_path=os.path.join(source_dir, modified_file_path),
                           old_flattened_dir=original_flattened_dir,
                           new_flattened_dir=modified_flattened_dir,
                           filename_prefix=platform_prefix)