MIPS: reland 16744: add context save for GenerateFastApiCall.

src/mips/code-stubs-mips.cc

Index: src/mips/code-stubs-mips.cc
diff --git a/src/mips/code-stubs-mips.cc b/src/mips/code-stubs-mips.cc
index e4f68f9d43077827379dc3b0688dc5b3dbc9bc01..ee49b25f45d5d4c1d9d20f8284caeee56df8d696 100644
--- a/src/mips/code-stubs-mips.cc
+++ b/src/mips/code-stubs-mips.cc
@@ -2876,7 +2876,7 @@ void CEntryStub::GenerateCore(MacroAssembler* masm,
   // v0:v1: result
   // sp: stack pointer
   // fp: frame pointer
-  __ LeaveExitFrame(save_doubles_, s0, true);
+  __ LeaveExitFrame(save_doubles_, s0, true, EMIT_RETURN);
 
   // Check if we should retry or throw exception.
   Label retry;
@@ -4156,7 +4156,7 @@ void RegExpExecStub::Generate(MacroAssembler* masm) {
   DirectCEntryStub stub;
   stub.GenerateCall(masm, t9);
 
-  __ LeaveExitFrame(false, no_reg);
+  __ LeaveExitFrame(false, no_reg, true);
 
   // v0: result
   // subject: subject string (callee saved)