dtrace: fix ustack helper for V8 5.1

V8 5.1 changes the layout of stack frames.

PR-URL: https://github.com/nodejs/node/pull/6482
Reviewed-By: bnoordhuis - Ben Noordhuis <info@bnoordhuis.nl>

src/v8abbr.h

@@ -86,8 +86,8 @@
     V8_OFF_HEAP(V8DBG_CLASS_JSFUNCTION__SHARED__SHAREDFUNCTIONINFO)
 #define V8_OFF_SHARED_NAME  \
     V8_OFF_HEAP(V8DBG_CLASS_SHAREDFUNCTIONINFO__NAME__OBJECT)
-#define V8_OFF_SHARED_INFERRED  \
-    V8_OFF_HEAP(V8DBG_CLASS_SHAREDFUNCTIONINFO__INFERRED_NAME__STRING)
+#define V8_OFF_SHARED_IDENT  \
+    V8_OFF_HEAP(V8DBG_CLASS_SHAREDFUNCTIONINFO__FUNCTION_IDENTIFIER__OBJECT)
 #define V8_OFF_SHARED_SCRIPT  \
     V8_OFF_HEAP(V8DBG_CLASS_SHAREDFUNCTIONINFO__SCRIPT__OBJECT)
 #define V8_OFF_SHARED_FUNTOK  \

src/v8ustack.d

@@ -414,7 +414,7 @@ dtrace:helper:ustack:
 dtrace:helper:ustack:
 /!this->done/
 {
-	this->marker = COPYIN_PTR(this->fp + V8_OFF_FP_MARKER);
+	this->marker = COPYIN_PTR(this->fp + V8_OFF_FP_CONTEXT);
 }
 
 dtrace:helper:ustack:
@@ -532,7 +532,7 @@ dtrace:helper:ustack:
 	APPEND_CHR('s');
 	APPEND_CHR(' ');
 
-	this->funcnamestr = COPYIN_PTR(this->shared + V8_OFF_SHARED_INFERRED);
+	this->funcnamestr = COPYIN_PTR(this->shared + V8_OFF_SHARED_IDENT);
 	LOAD_STRFIELDS(this->funcnamestr, this->funcnamelen,
 	    this->funcnameattrs);
 }