Turn some usages of NewArray with DeleteArray in the same scope into ScopedVector or SmartPointer.

src/platform-macos.cc

Index: src/platform-macos.cc
diff --git a/src/platform-macos.cc b/src/platform-macos.cc
index 551690989fd3057a14594fbbd06b141bcef0bd45..14207b0a6ac565fac769cf3f331cb9de80a561ff 100644
--- a/src/platform-macos.cc
+++ b/src/platform-macos.cc
@@ -283,13 +283,12 @@ int OS::StackWalk(Vector<StackFrame> frames) {
     return 0;
 
   int frames_size = frames.length();
-  void** addresses = NewArray<void*>(frames_size);
-  int frames_count = backtrace(addresses, frames_size);
+  ScopedVector<void*> addresses(frames_size);
 
-  char** symbols;
-  symbols = backtrace_symbols(addresses, frames_count);
+  int frames_count = backtrace(addresses.start(), frames_size.start());
+
+  char** symbols = backtrace_symbols(addresses.start(), frames_count);
   if (symbols == NULL) {
-    DeleteArray(addresses);
     return kStackWalkError;
   }
 
@@ -305,7 +304,6 @@ int OS::StackWalk(Vector<StackFrame> frames) {
     frames[i].text[kStackWalkMaxTextLen - 1] = '\0';
   }
 
-  DeleteArray(addresses);
   free(symbols);
 
   return frames_count;