Do not leak message object beyond try-catch.

src/mips/full-codegen-mips.cc

Index: src/mips/full-codegen-mips.cc
diff --git a/src/mips/full-codegen-mips.cc b/src/mips/full-codegen-mips.cc
index 67ec571296af847d2c6d63f1b967803d5cb764e0..fea797e7a4bf3c23519193d834c3cda145cc0abe 100644
--- a/src/mips/full-codegen-mips.cc
+++ b/src/mips/full-codegen-mips.cc
@@ -5353,6 +5353,8 @@ void FullCodeGenerator::EnterFinallyBlock() {
   __ li(at, Operand(pending_message_obj));
   __ lw(a1, MemOperand(at));
   __ push(a1);
+
+  ClearPendingMessage();
 }
 
 
@@ -5377,6 +5379,16 @@ void FullCodeGenerator::ExitFinallyBlock() {
 }
 
 
+void FullCodeGenerator::ClearPendingMessage() {
+  DCHECK(!result_register().is(a1));
+  ExternalReference pending_message_obj =
+      ExternalReference::address_of_pending_message_obj(isolate());
+  __ LoadRoot(a1, Heap::kTheHoleValueRootIndex);
+  __ li(at, Operand(pending_message_obj));
+  __ sw(a1, MemOperand(at));
+}
+
+
 #undef __