Add line counts to data model

python/helpers/profiler/profiler.thrift

@@ -23,6 +23,7 @@ struct CallTreeStat {
   1: required i32 count,
   2: required string name,
   3: required list<CallTreeStat> children,
+  4: required map<i32, i32> line_count,    // number of times a line inside the frame was executed
 }
 
 struct TreeStats {

python/helpers/profiler/vmprof_profiler.py

@@ -88,6 +88,7 @@ def tree_stats_to_response(filename, response):
         tstats.name = node.name
         tstats.count = node.count
         tstats.children = []
+        tstats.line_count = {}
 
         if parent is not None:
             if parent.children is None: