Revert "Make GCC happy again." and "Initial switch to Chromium-style CHECK_* and DCHECK_* macros.".

src/arm/macro-assembler-arm.h

Index: src/arm/macro-assembler-arm.h
diff --git a/src/arm/macro-assembler-arm.h b/src/arm/macro-assembler-arm.h
index 9d46165ecaf53e3d0f5b89b45aa9fcf76727513b..88a68a90c2aa49f4bde29f8cd973755c609f529f 100644
--- a/src/arm/macro-assembler-arm.h
+++ b/src/arm/macro-assembler-arm.h
@@ -944,7 +944,7 @@ class MacroAssembler: public Assembler {
     ldr(type, FieldMemOperand(obj, HeapObject::kMapOffset), cond);
     ldrb(type, FieldMemOperand(type, Map::kInstanceTypeOffset), cond);
     tst(type, Operand(kIsNotStringMask), cond);
-    DCHECK_EQ(0u, kStringTag);
+    DCHECK_EQ(0, kStringTag);
     return eq;
   }