MIPS: Fix Kraken gaussian blur test regression.

src/mips/lithium-codegen-mips.cc

Index: src/mips/lithium-codegen-mips.cc
diff --git a/src/mips/lithium-codegen-mips.cc b/src/mips/lithium-codegen-mips.cc
index 044b9c7c6d70c77903c9f2f3388145744db9a34f..ccf633b3a77fa84a455c0627a9483630847a23a6 100644
--- a/src/mips/lithium-codegen-mips.cc
+++ b/src/mips/lithium-codegen-mips.cc
@@ -3627,6 +3627,7 @@ void LCodeGen::EmitIntegerMathAbs(LMathAbs* instr) {
   Label done;
   __ Branch(USE_DELAY_SLOT, &done, ge, input, Operand(zero_reg));
   __ mov(result, input);
+  __ subu(result, zero_reg, input);
   // Overflow if result is still negative, i.e. 0x80000000.
   DeoptimizeIf(lt, instr->environment(), result, Operand(zero_reg));
   __ bind(&done);