MIPS: Fix trampoline pool handling in MacroAssembler::BranchShort()

BUG=chromium:555543
LOG=N

Review URL: https://codereview.chromium.org/1448033002

Cr-Commit-Position: refs/heads/master@{#32017}

src/mips/macro-assembler-mips.cc

@@ -2374,6 +2374,7 @@ bool MacroAssembler::BranchShortHelper(int16_t offset, Label* L, Condition cond,
   // Be careful to always use shifted_branch_offset only just before the
   // branch instruction, as the location will be remember for patching the
   // target.
+  {
     BlockTrampolinePoolScope block_trampoline_pool(this);
     switch (cond) {
       case cc_always:
@@ -2488,7 +2489,7 @@ bool MacroAssembler::BranchShortHelper(int16_t offset, Label* L, Condition cond,
       default:
         UNREACHABLE();
     }
-
+  }
   // Emit a nop in the branch delay slot if required.
   if (bdslot == PROTECT)
     nop();