Enabled incrementals to patch + rename moved files

Change-Id: I551fc5291847e3ace15361c203d86f566c26da97
diff --git a/tools/releasetools/edify_generator.py b/tools/releasetools/edify_generator.py
index 2c3b9e7..426b713 100644
--- a/tools/releasetools/edify_generator.py
+++ b/tools/releasetools/edify_generator.py
@@ -184,6 +184,20 @@
     cmd = "delete(" + ",\0".join(['"%s"' % (i,) for i in file_list]) + ");"
     self.script.append(self._WordWrap(cmd))
 
+  def RenameFile(self, srcfile, tgtfile):
+    """Moves a file from one location to another."""
+    if self.info.get("update_rename_support", False):
+      self.script.append('rename("%s", "%s");' % (srcfile, tgtfile))
+    else:
+      raise ValueError("Rename not supported by update binary")
+
+  def SkipNextActionIfTargetExists(self, tgtfile, tgtsha1):
+    """Prepend an action with an apply_patch_check in order to
+       skip the action if the file exists.  Used when a patch
+       is later renamed."""
+    cmd = ('sha1_check(read_file("%s"), %s) || ' % (tgtfile, tgtsha1))
+    self.script.append(self._WordWrap(cmd))
+
   def ApplyPatch(self, srcfile, tgtfile, tgtsize, tgtsha1, *patchpairs):
     """Apply binary patches (in *patchpairs) to the given srcfile to
     produce tgtfile (which may be "-" to indicate overwriting the