[perf-web] More fixes for more data

[Owen Taylor <otaylor src gnome org>]

commit 0107ecb84bd8f474a44ecb56aff5ba4b5139b517
Author: Owen W. Taylor <otaylor fishsoup net>
Date:   Tue Jul 22 21:08:01 2014 -0400

    More fixes for more data
    
    Fix some other places where we would backtrace if there was no data.

 metrics/views.py |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)
---
diff --git a/metrics/views.py b/metrics/views.py
index beb4b92..88a54dd 100644
--- a/metrics/views.py
+++ b/metrics/views.py
@@ -54,6 +54,8 @@ def metric(request, metric_name):
     t = loader.get_template('metrics/metric.html')
     time_range = Report.objects \
                    .aggregate(min=Min('pull_time'), max=Max('pull_time'));
+    if time_range['min'] is None:
+        time_range['min'] = time_range['max'] = datetime.now()
 
     c = Context({
         'page_name': 'metric',
@@ -75,6 +77,8 @@ def target(request, machine_name, partition_name, tree_name, testset_name):
     time_range = Report.objects \
                    .filter(target__name=target.name) \
                    .aggregate(min=Min('pull_time'), max=Max('pull_time'));
+    if time_range['min'] is None:
+        time_range['min'] = time_range['max'] = datetime.now()
 
     c = Context({
         'page_name': 'target',