caches: invalidate store caches when lock is taken

caches: invalidate store caches when lock is taken

The fncache was not being properly invalidated each time the lock was taken, so
in theory it could contain old data from prior to the caller having the lock.
This changes it to be invalidated as soon as the lock is taken (same as all our
other caches).

--- a/mercurial/localrepo.py	Mon Mar 24 15:42:13 2014 -0700
+++ b/mercurial/localrepo.py	Mon Mar 24 15:35:07 2014 -0700
@@ -996,6 +996,7 @@
             except AttributeError:
                 pass
         self.invalidatecaches()
+        self.store.invalidatecaches()
 
     def invalidateall(self):
         '''Fully invalidates both store and non-store parts, causing the

--- a/mercurial/store.py	Mon Mar 24 15:42:13 2014 -0700
+++ b/mercurial/store.py	Mon Mar 24 15:35:07 2014 -0700
@@ -340,6 +340,9 @@
     def write(self, tr):
         pass
 
+    def invalidatecaches(self):
+        pass
+
     def __contains__(self, path):
         '''Checks if the store contains path'''
         path = "/".join(("data", path))
@@ -489,6 +492,9 @@
     def write(self, tr):
         self.fncache.write(tr)
 
+    def invalidatecaches(self):
+        self.fncache.entries = None
+
     def _exists(self, f):
         ef = self.encode(f)
         try: