Fix break location calculation.

R=ulan@chromium.org
BUG=chromium:419663
LOG=Y

Review URL: https://codereview.chromium.org/658723005

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24697 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/debug.cc

@@ -1096,7 +1096,7 @@ bool Debug::SetBreakPoint(Handle<JSFunction> function,
   it.FindBreakLocationFromPosition(*source_position, STATEMENT_ALIGNED);
   it.SetBreakPoint(break_point_object);
 
-  *source_position = it.position();
+  *source_position = it.statement_position();
 
   // At least one active break point now.
   return debug_info->GetBreakPointCount() > 0;
@@ -1140,7 +1140,10 @@ bool Debug::SetBreakPointForScript(Handle<Script> script,
   it.FindBreakLocationFromPosition(position, alignment);
   it.SetBreakPoint(break_point_object);
 
-  *source_position = it.position() + shared->start_position();
+  position = (alignment == STATEMENT_ALIGNED) ? it.statement_position()
+                                              : it.position();
+
+  *source_position = position + shared->start_position();
 
   // At least one active break point now.
   DCHECK(debug_info->GetBreakPointCount() > 0);
@@ -1566,9 +1569,6 @@ Handle<Object> Debug::GetSourceBreakLocations(
         case BREAK_POSITION_ALIGNED:
           position = break_point_info->source_position();
           break;
-        default:
-          UNREACHABLE();
-          position = break_point_info->statement_position();
         }
 
         locations->set(count++, position);

test/mjsunit/regress/regress-419663.js

+// 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.
+
+// Flags: --expose-debug-as debug
+
+var o = {
+  f: function(x) {
+    var a = x + 1;
+    o = 1;
+  }
+}
+
+function sentinel() {}
+
+var Debug = debug.Debug;
+
+Debug.setListener(function() {});
+
+var script = Debug.findScript(sentinel);
+
+// Used in Debug.setScriptBreakPointById.
+var p = Debug.findScriptSourcePosition(script, 9, 0);
+var q = Debug.setBreakPointByScriptIdAndPosition(script.id, p).actual_position;
+var r = Debug.setBreakPointByScriptIdAndPosition(script.id, q).actual_position;
+
+assertEquals(q, r);
+
+function assertLocation(p, l, c) {
+  var location = script.locationFromPosition(p, false);
+  assertEquals(l, location.line);
+  assertEquals(c, location.column);
+}
+
+assertLocation(p, 9, 0);
+assertLocation(q, 9, 4);
+assertLocation(r, 9, 4);