Clean up temp dirs when breaking locks.

A number of bots have been running out of disk space because they
are accumulating temp dirs and temp pack files.  Be more careful
to clean up temp dirs whenever UnlockAll() is called.

R=hinoka@chromium.org,agable@chromium.org
BUG=

Review URL: https://codereview.chromium.org/335253002

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@277812 0039d316-1c4b-4281-b951-d872f2087c98

git_cache.py

@@ -278,7 +278,7 @@ class Mirror(object):
 
     # Download zip file to a temporary directory.
     try:
-      tempdir = tempfile.mkdtemp()
+      tempdir = tempfile.mkdtemp(prefix='_cache_tmp', dir=self.GetCachePath())
       self.print('Downloading %s' % latest_checkout)
       code = gsutil.call('cp', latest_checkout, tempdir)
       if code:
@@ -344,7 +344,7 @@ class Mirror(object):
                           len(pack_files) > GC_AUTOPACKLIMIT)
       if should_bootstrap:
         tempdir = tempfile.mkdtemp(
-            suffix=self.basedir, dir=self.GetCachePath())
+            prefix='_cache_tmp', suffix=self.basedir, dir=self.GetCachePath())
         bootstrapped = not depth and bootstrap and self.bootstrap_repo(tempdir)
         if bootstrapped:
           # Bootstrap succeeded; delete previous cache, if any.
@@ -408,8 +408,8 @@ class Mirror(object):
       except OSError:
         logging.warn('Unable to delete temporary pack file %s' % f)
 
-  @staticmethod
-  def BreakLocks(path):
+  @classmethod
+  def BreakLocks(cls, path):
     did_unlock = False
     lf = Lockfile(path)
     if lf.break_lock():
@@ -420,6 +420,7 @@ class Mirror(object):
     if os.path.exists(lf):
       os.remove(lf)
       did_unlock = True
+    cls.DeleteTmpPackFiles(path)
     return did_unlock
 
   def unlock(self):
@@ -432,7 +433,9 @@ class Mirror(object):
     repo_dirs = set([os.path.join(cachepath, path) for path in dirlist
                      if os.path.isdir(os.path.join(cachepath, path))])
     for dirent in dirlist:
-      if (dirent.endswith('.lock') and
+      if dirent.startswith('_cache_tmp') or dirent.startswith('tmp'):
+        gclient_utils.rmtree(os.path.join(cachepath, dirent))
+      elif (dirent.endswith('.lock') and
           os.path.isfile(os.path.join(cachepath, dirent))):
         repo_dirs.add(os.path.join(cachepath, dirent[:-5]))