Reenable DoStoreContextSlot, I can't reproduce any local bugs on this.

Review URL: http://codereview.chromium.org/6588082

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@6996 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/x64/lithium-x64.cc

@@ -1726,7 +1726,6 @@ LInstruction* LChunkBuilder::DoLoadContextSlot(HLoadContextSlot* instr) {
 
 
 LInstruction* LChunkBuilder::DoStoreContextSlot(HStoreContextSlot* instr) {
-  Abort("Unimplemented: DoStoreContextSlot");  // Temporarily disabled (whesse).
   LOperand* context;
   LOperand* value;
   if (instr->NeedsWriteBarrier()) {