[Findit] Initial code of findit for crash. Add scorers to apply heuristic rules.

appengine/findit/common/chromium_deps.py

Index: appengine/findit/common/chromium_deps.py
diff --git a/appengine/findit/common/chromium_deps.py b/appengine/findit/common/chromium_deps.py
index b402827c4307ce6ad09ed63cfe942ae08d797b40..50c58709110884e8607548e7dd83f3da1e97a905 100644
--- a/appengine/findit/common/chromium_deps.py
+++ b/appengine/findit/common/chromium_deps.py
@@ -114,3 +114,29 @@ def GetChromiumDEPSRolls(old_cr_revision, new_cr_revision, os_platform,
               path, old_dep.repo_url, old_dep.revision, None))
 
   return rolls
+
+
+def GetDEPSRollsDict(old_cr_revision, new_cr_revision, os_platform):
+  """Get dep_path to DependencyRoll dictionary for deps in

[stgao, 2016/04/15 18:35:18]

nit: One line summary here.
nit: "Get" -> "Gets".

Let's try to be consistent with other code in the repo.

[Sharu, 2016/04/15 22:59:46]

Ouch, didn't catch this.

Done.

+  (old_cr_revision, new_cr_revision].
+
+  Args:
+    old_cr_revision (str): The Git commit hash for the old Chromium revision.
+    new_cr_revision (str): The Git commit hash for the new Chromium revision.
+    os_platform (str): The target OS platform of the Chrome or test binary.
+
+  Returns:
+    A dict, mapping dep path to DependencyRoll.
+  """
+  deps_rolls = GetChromiumDEPSRolls(old_cr_revision, new_cr_revision,
+                                    os_platform)
+  # Add chromium as dependency roll.
+  deps_rolls.append(dependency.DependencyRoll(
+      _CHROMIUM_ROOT_DIR, _CHROMIUM_REPO_MASTER,
+      old_cr_revision, new_cr_revision))
+
+  dependency_rolls = {}
+  for dep_roll in deps_rolls:
+    dependency_rolls[dep_roll.path] = dep_roll
+
+  return dependency_rolls