[debug] Reland debug API removal

src/execution.cc

Index: src/execution.cc
diff --git a/src/execution.cc b/src/execution.cc
index 59421c70bef54d2c0e8466fa71fc567d94cdc8d2..e95b502e05adaafcf16f6dbd3563161efc7463d0 100644
--- a/src/execution.cc
+++ b/src/execution.cc
@@ -451,7 +451,7 @@ Object* StackGuard::HandleInterrupts() {
     isolate_->heap()->HandleGCRequest();
   }
 
-  if (CheckDebugBreak() || CheckDebugCommand()) {
+  if (CheckDebugBreak()) {
     isolate_->debug()->HandleDebugBreak();
   }