Revert r12625 due to sandbox incompatibility.

src/platform-freebsd.cc

Index: src/platform-freebsd.cc
diff --git a/src/platform-freebsd.cc b/src/platform-freebsd.cc
index 7d41f37083fdd429c946c8823ce71504a161bb7a..511759c485e245891dd41a2fa792128e91915f91 100644
--- a/src/platform-freebsd.cc
+++ b/src/platform-freebsd.cc
@@ -456,13 +456,6 @@ bool VirtualMemory::ReleaseRegion(void* base, size_t size) {
 }
 
 
-bool VirtualMemory::CommittedPhysicalSizeInRegion(
-    void* base, size_t size, size_t* physical) {
-  // TODO(alph): implement for the platform.
-  return false;
-}
-
-
 class Thread::PlatformData : public Malloced {
  public:
   pthread_t thread_;  // Thread handle for pthread.