Always initialize the debugger eagerly.

src/arm/debug-arm.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "v8.h"
 
 #if V8_TARGET_ARCH_ARM
 
 #include "codegen.h"
 #include "debug.h"
@@ skipping 14 matching lines @@
   //   bx lr
   // to a call to the debug break return code.
   //   ldr ip, [pc, #0]
   //   blx ip
   //   <debug break return code entry point address>
   //   bktp 0
   CodePatcher patcher(rinfo()->pc(), Assembler::kJSReturnSequenceInstructions);
   patcher.masm()->ldr(v8::internal::ip, MemOperand(v8::internal::pc, 0));
   patcher.masm()->blx(v8::internal::ip);
   patcher.Emit(
-      debug_info_->GetIsolate()->debug()->debug_break_return()->entry());
+      debug_info_->GetIsolate()->builtins()->Return_DebugBreak()->entry());
   patcher.masm()->bkpt(0);
 }
 
 
 // Restore the JS frame exit code.
 void BreakLocationIterator::ClearDebugBreakAtReturn() {
   rinfo()->PatchCode(original_rinfo()->pc(),
                      Assembler::kJSReturnSequenceInstructions);
 }
 
@@ skipping 20 matching lines @@
   //   mov r2, r2
   //   mov r2, r2
   // to a call to the debug break slot code.
   //   ldr ip, [pc, #0]
   //   blx ip
   //   <debug break slot code entry point address>
   CodePatcher patcher(rinfo()->pc(), Assembler::kDebugBreakSlotInstructions);
   patcher.masm()->ldr(v8::internal::ip, MemOperand(v8::internal::pc, 0));
   patcher.masm()->blx(v8::internal::ip);
   patcher.Emit(
-      debug_info_->GetIsolate()->debug()->debug_break_slot()->entry());
+      debug_info_->GetIsolate()->builtins()->Slot_DebugBreak()->entry());
 }
 
 
 void BreakLocationIterator::ClearDebugBreakAtSlot() {
   ASSERT(IsDebugBreakSlot());
   rinfo()->PatchCode(original_rinfo()->pc(),
                      Assembler::kDebugBreakSlotInstructions);
 }
 
 const bool Debug::FramePaddingLayout::kIsSupported = false;
@@ skipping 204 matching lines @@
   masm->Abort(kLiveEditFrameDroppingIsNotSupportedOnArm);
 }
 
 const bool Debug::kFrameDropperSupported = false;
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM