Reapply "Clean up Context::Lookup and its uses."

src/hydrogen.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 4904 matching lines @@
       return;
 
     } else {
       HValue* context = environment()->LookupContext();
       call = PreProcessCall(
           new(zone()) HCallNamed(context, name, argument_count));
     }
 
   } else {
     VariableProxy* proxy = expr->expression()->AsVariableProxy();
-    // FIXME.
     bool global_call = proxy != NULL && proxy->var()->IsUnallocated();
 
     if (global_call) {
       Variable* var = proxy->var();
       bool known_global_function = false;
       // If there is a global property cell for the name at compile time and
       // access check is not enabled we assume that the function will not change
       // and generate optimized code for calling the function.
       LookupResult lookup;
       GlobalPropertyAccess type = LookupGlobalProperty(var, &lookup, false);
@@ skipping 1876 matching lines @@
     }
   }
 
 #ifdef DEBUG
   if (graph_ != NULL) graph_->Verify();
   if (allocator_ != NULL) allocator_->Verify();
 #endif
 }
 
 } }  // namespace v8::internal