Fix assignment compilation bug on ARM and x64.

SVN revision 5993 ported changes to the unoptimizing compiler from
ia32 to ARM and x64.  A call to AstContext::Plug was moved out of
FullCodeGenerator::EmitVariableAssignment and into the callers.  One
call site was missed in both ports.

Review URL: http://codereview.chromium.org/5781008

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@6003 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/arm/full-codegen-arm.cc

@@ -1489,6 +1489,8 @@ void FullCodeGenerator::VisitAssignment(Assignment* expr) {
     case VARIABLE:
       EmitVariableAssignment(expr->target()->AsVariableProxy()->var(),
                              expr->op());
+      PrepareForBailoutForId(expr->AssignmentId(), TOS_REG);
+      context()->Plug(r0);
       break;
     case NAMED_PROPERTY:
       EmitNamedPropertyAssignment(expr);

src/x64/full-codegen-x64.cc

@@ -1415,6 +1415,7 @@ void FullCodeGenerator::VisitAssignment(Assignment* expr) {
     case VARIABLE:
       EmitVariableAssignment(expr->target()->AsVariableProxy()->var(),
                              expr->op());
+      context()->Plug(rax);
       break;
     case NAMED_PROPERTY:
       EmitNamedPropertyAssignment(expr);