Modify release tools to replace certs in MMAC files.

Added support to perform a string replace of specified
dev keys with release keys when using the release tool
scripts.

Signed-off-by: rpcraig <rpcraig@tycho.ncsc.mil>

(cherry picked from commit 817c574d753191c52acd5787da02bb853d4ac090)

Change-Id: I51be8d62945436d3f374f51867295c5b792d4b53
Bug: 11334314
diff --git a/tools/releasetools/check_target_files_signatures b/tools/releasetools/check_target_files_signatures
index ae372ba..45d30a6 100755
--- a/tools/releasetools/check_target_files_signatures
+++ b/tools/releasetools/check_target_files_signatures
@@ -135,7 +135,7 @@
 
     for i in to_load:
       f = open(i)
-      cert = ParseCertificate(f.read())
+      cert = common.ParseCertificate(f.read())
       f.close()
       name, _ = os.path.splitext(i)
       name, _ = os.path.splitext(name)
@@ -144,21 +144,6 @@
 ALL_CERTS = CertDB()
 
 
-def ParseCertificate(data):
-  """Parse a PEM-format certificate."""
-  cert = []
-  save = False
-  for line in data.split("\n"):
-    if "--END CERTIFICATE--" in line:
-      break
-    if save:
-      cert.append(line)
-    if "--BEGIN CERTIFICATE--" in line:
-      save = True
-  cert = "".join(cert).decode('base64')
-  return cert
-
-
 def CertFromPKCS7(data, filename):
   """Read the cert out of a PKCS#7-format file (which is what is
   stored in a signed .apk)."""
@@ -175,7 +160,7 @@
       AddProblem("error reading cert:\n" + err)
       return None
 
-    cert = ParseCertificate(out)
+    cert = common.ParseCertificate(out)
     if not cert:
       AddProblem("error parsing cert output")
       return None