Revert "Add support for trace event processing using callacks"

This reverts commit 2b9b25c74416328a0f68af5b60b73534e4ccbd02.
diff --git a/tests/test_ftrace.py b/tests/test_ftrace.py
index 9f09e8e..7d7874a 100644
--- a/tests/test_ftrace.py
+++ b/tests/test_ftrace.py
@@ -230,31 +230,6 @@
         # Make sure there are no NaNs in the middle of the array
         self.assertTrue(allfreqs[0][1]["A57_freq_in"].notnull().all())
 
-    def test_run_event_callbacks(self):
-        """Test run_event_callbacks()"""
-
-        counts = {
-            "cpu_in_power": 0,
-            "cpu_out_power": 0
-        }
-
-        def cpu_in_power_fn(data):
-            counts["cpu_in_power"] += 1
-
-        def cpu_out_power_fn(data):
-            counts["cpu_out_power"] += 1
-
-        fn_map = {
-            "cpu_in_power": cpu_in_power_fn,
-            "cpu_out_power": cpu_out_power_fn
-        }
-        trace = trappy.FTrace()
-
-        trace.run_event_callbacks(fn_map)
-
-        self.assertEqual(counts["cpu_in_power"], 134)
-        self.assertEqual(counts["cpu_out_power"], 134)
-
     def test_plot_freq_hists(self):
         """Test that plot_freq_hists() doesn't bomb"""
 
diff --git a/trappy/ftrace.py b/trappy/ftrace.py
index e308398..07e01c7 100644
--- a/trappy/ftrace.py
+++ b/trappy/ftrace.py
@@ -309,55 +309,6 @@
 
         return ret
 
-    def run_event_callbacks(self, fn_map):
-        """
-        Apply callback functions to trace events in chronological order.
-
-        This method iterates over a user-specified subset of the available trace
-        event dataframes, calling different user-specified functions for each
-        event type. These functions are passed a dictionary mapping 'Index' and
-        the column names to their values for that row.
-
-        For example, to iterate over trace t, applying your functions callback_fn1
-        and callback_fn2 to each sched_switch and sched_wakeup event respectively:
-
-        t.run_event_callbacks({
-            "sched_switch": callback_fn1,
-            "sched_wakeup": callback_fn2
-        })
-        """
-        dfs = {event: getattr(self, event).data_frame for event in fn_map.keys()}
-        events = [event for event in fn_map.keys() if not dfs[event].empty]
-        iters = {event: dfs[event].itertuples() for event in events}
-        next_rows = {event: iterator.next() for event,iterator in iters.iteritems()}
-
-        # Column names beginning with underscore will not be preserved in tuples
-        # due to constraints on namedtuple field names, so store mappings from
-        # column name to column number for each trace event.
-        col_idxs = {event: {
-            name: idx for idx, name in enumerate(
-                ['Index'] + dfs[event].columns.tolist()
-            )
-        } for event in events}
-
-        def getLine(event):
-            line_col_idx = col_idxs[event]['__line']
-            return next_rows[event][line_col_idx]
-
-        while events:
-            event_name = min(events, key=getLine)
-            event_tuple = next_rows[event_name]
-
-            event_dict = {
-                col: event_tuple[idx] for col, idx in col_idxs[event_name].iteritems()
-            }
-            fn_map[event_name](event_dict)
-            event_row = next(iters[event_name], None)
-            if event_row:
-                next_rows[event_name] = event_row
-            else:
-                events.remove(event_name)
-
     def plot_freq_hists(self, map_label, ax):
         """Plot histograms for each actor input and output frequency