Fix issues with gathering third party repositories for bisect.

tools/bisect-perf-regression.py

Index: tools/bisect-perf-regression.py
diff --git a/tools/bisect-perf-regression.py b/tools/bisect-perf-regression.py
index 51e639fbcbc125128bd727924118b5ac903595fa..6e7e0198e57982d7b8a76621ab8cec7f4574d4a8 100755
--- a/tools/bisect-perf-regression.py
+++ b/tools/bisect-perf-regression.py
@@ -1429,7 +1429,8 @@ class BisectPerformanceMetrics(object):
           continue
 
         if (depot_data.get('recurse') and depot in depot_data.get('from')):
-          src_dir = depot_data.get('src') or depot_data.get('src_old')
+          src_dir = (deps_data.get(depot_data.get('src')) or
+                     deps_data.get(depot_data.get('src_old')))
           if src_dir:
             self.depot_cwd[depot_name] = os.path.join(self.src_cwd, src_dir[4:])
             re_results = rxp.search(deps_data.get(src_dir, ''))
@@ -1440,6 +1441,8 @@ class BisectPerformanceMetrics(object):
                              '%s' % (depot_name, depot))
               if not warning_text in self.warnings:
                 self.warnings.append(warning_text)
+          else:
+            results[depot_name] = None
       return results
     except ImportError:
       deps_file_contents = ReadStringFromFile(bisect_utils.FILE_DEPS_GIT)
@@ -2536,12 +2539,12 @@ class BisectPerformanceMetrics(object):
         # backwards to try to match trunk revisions to bleeding_edge.
         self._FillInV8BleedingEdgeInfo(min_revision_data, max_revision_data)
 
-      if (min_revision_data['external'][next_depot] ==
-          max_revision_data['external'][next_depot]):
+      if (min_revision_data['external'].get(next_depot) ==
+          max_revision_data['external'].get(next_depot)):
         continue
 
-      if (min_revision_data['external'][next_depot] and
-          max_revision_data['external'][next_depot]):
+      if (min_revision_data['external'].get(next_depot) and
+          max_revision_data['external'].get(next_depot)):
         external_depot = next_depot
         break