PredictableCodeSizeScope checks the expected size now.

src/arm/lithium-codegen-arm.cc

Index: src/arm/lithium-codegen-arm.cc
diff --git a/src/arm/lithium-codegen-arm.cc b/src/arm/lithium-codegen-arm.cc
index be107d60420ac702cde2bbc456bd6a017e6f0753..94e5b576b7d7925250781f3c921dda7fd70296c4 100644
--- a/src/arm/lithium-codegen-arm.cc
+++ b/src/arm/lithium-codegen-arm.cc
@@ -2547,7 +2547,7 @@ void LCodeGen::DoInstanceOfKnownGlobal(LInstanceOfKnownGlobal* instr) {
     // We use Factory::the_hole_value() on purpose instead of loading from the
     // root array to force relocation to be able to later patch with
     // the cached map.
-    PredictableCodeSizeScope predictable(masm_);
+    PredictableCodeSizeScope predictable(masm_, 5 * Assembler::kInstrSize);
     Handle<JSGlobalPropertyCell> cell =
         factory()->NewJSGlobalPropertyCell(factory()->the_hole_value());
     __ mov(ip, Operand(Handle<Object>(cell)));
@@ -2611,7 +2611,7 @@ void LCodeGen::DoDeferredInstanceOfKnownGlobal(LInstanceOfKnownGlobal* instr,
   static const int kAdditionalDelta = 5;
   // Make sure that code size is predicable, since we use specific constants
   // offsets in the code to find embedded values..
-  PredictableCodeSizeScope predictable(masm_);
+  PredictableCodeSizeScope predictable(masm_, 6 * Assembler::kInstrSize);
   int delta = masm_->InstructionsGeneratedSince(map_check) + kAdditionalDelta;
   Label before_push_delta;
   __ bind(&before_push_delta);
@@ -5640,7 +5640,7 @@ void LCodeGen::DoStackCheck(LStackCheck* instr) {
     __ cmp(sp, Operand(ip));
     __ b(hs, &done);
     StackCheckStub stub;
-    PredictableCodeSizeScope predictable(masm_);
+    PredictableCodeSizeScope predictable(masm_, 2 * Assembler::kInstrSize);
     CallCode(stub.GetCode(), RelocInfo::CODE_TARGET, instr);
     EnsureSpaceForLazyDeopt();
     __ bind(&done);