Fixed a ton of Python lint errors, enabled python lint checking.

BUG=

Review URL: https://webrtc-codereview.appspot.com/1166004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@3627 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/tools/python_charts/webrtc/main.py b/tools/python_charts/webrtc/main.py
index 82d8831..c2e2b82 100644
--- a/tools/python_charts/webrtc/main.py
+++ b/tools/python_charts/webrtc/main.py
@@ -7,30 +7,28 @@
 #  in the file PATENTS.  All contributing project authors may
 #  be found in the AUTHORS file in the root of the source tree.
 
-__author__ = 'kjellander@webrtc.org (Henrik Kjellander)'
-
 import os
 import gviz_api
 import webrtc.data_helper
 
 def main():
   """
-  This Python script displays a web page with test created with the 
+  This Python script displays a web page with test created with the
   video_quality_measurement program, which is a tool in WebRTC.
-  
+
   The script requires on two external files and one Python library:
-  - A HTML template file with layout and references to the json variables 
+  - A HTML template file with layout and references to the json variables
     defined in this script
   - A data file in Python format, containing the following:
     - test_configuration - a dictionary of test configuration names and values.
-    - frame_data_types - a dictionary that maps the different metrics to their 
+    - frame_data_types - a dictionary that maps the different metrics to their
       data types.
-    - frame_data - a list of dictionaries where each dictionary maps a metric to 
-      it's value. 
+    - frame_data - a list of dictionaries where each dictionary maps a metric to
+      it's value.
   - The gviz_api.py of the Google Visualization Python API, available at
     http://code.google.com/p/google-visualization-python/
-  
-  The HTML file is shipped with the script, while the data file must be 
+
+  The HTML file is shipped with the script, while the data file must be
   generated by running video_quality_measurement with the --python flag
   specified.
   """
@@ -48,78 +46,78 @@
     page_template = f.read()
     f.close()
   except IOError as e:
-    ShowErrorPage('Cannot open page template file: %s<br>Details: %s' % 
+    ShowErrorPage('Cannot open page template file: %s<br>Details: %s' %
                   (page_template_filename, e))
     return
-  
+
   # Read data from external Python script files. First check that they exist.
   for filename in data_filenames:
     if not os.path.exists(filename):
       messages.append('Cannot open data file: %s' % filename)
       data_filenames.remove(filename)
-  
+
   # Read data from all existing input files.
   data_list = []
   test_configurations = []
   names = []
-  
+
   for filename in data_filenames:
     read_vars = {} # empty dictionary to load the data into.
     execfile(filename, read_vars, read_vars)
-    
+
     test_configuration = read_vars['test_configuration']
     table_description = read_vars['frame_data_types']
     table_data = read_vars['frame_data']
-    
+
     # Verify the data in the file loaded properly.
     if not table_description or not table_data:
       messages.append('Invalid input file: %s. Missing description list or '
                       'data dictionary variables.' % filename)
       continue
-    
+
     # Frame numbers appear as number type in the data, but Chart API requires
     # values of the X-axis to be of string type.
-    # Change the frame_number column data type: 
+    # Change the frame_number column data type:
     table_description['frame_number'] = ('string', 'Frame number')
-    # Convert all the values to string types: 
+    # Convert all the values to string types:
     for row in table_data:
       row['frame_number'] = str(row['frame_number'])
-    
+
     # Store the unique data from this file in the high level lists.
     test_configurations.append(test_configuration)
     data_list.append(table_data)
     # Name of the test run must be present.
     test_name = FindConfiguration(test_configuration, 'name')
     if not test_name:
-      messages.append('Invalid input file: %s. Missing configuration key ' 
+      messages.append('Invalid input file: %s. Missing configuration key '
                       '"name"', filename)
       continue
     names.append(test_name)
-    
+
   # Create data helper and build data tables for each graph.
-  helper = webrtc.data_helper.DataHelper(data_list, table_description, 
+  helper = webrtc.data_helper.DataHelper(data_list, table_description,
                                          names, messages)
-    
+
   # Loading it into gviz_api.DataTable objects and create JSON strings.
   description, data = helper.CreateConfigurationTable(test_configurations)
   configurations = gviz_api.DataTable(description, data)
   json_configurations = configurations.ToJSon()
-  
+
   description, data = helper.CreateData('ssim')
   ssim = gviz_api.DataTable(description, data)
   json_ssim_data = ssim.ToJSon(helper.GetOrdering(description))
-  
+
   description, data = helper.CreateData('psnr')
   psnr = gviz_api.DataTable(description, data)
   json_psnr_data = psnr.ToJSon(helper.GetOrdering(description))
-  
+
   description, data = helper.CreateData('packets_dropped')
   packet_loss = gviz_api.DataTable(description, data)
-  json_packet_loss_data = packet_loss.ToJSon(helper.GetOrdering(description))  
-  
+  json_packet_loss_data = packet_loss.ToJSon(helper.GetOrdering(description))
+
   description, data = helper.CreateData('bit_rate')
   # Add a column of data points for the desired bit rate to be plotted.
-  # (uses test configuration from the last data set, assuming it is the same 
+  # (uses test configuration from the last data set, assuming it is the same
   # for all of them)
   desired_bit_rate = FindConfiguration(test_configuration, 'bit_rate_in_kbps')
   if not desired_bit_rate:
@@ -135,12 +133,12 @@
 
   # Format the messages list with newlines.
   messages = '\n'.join(messages)
-  
+
   # Put the variables as JSon strings into the template.
   print page_template % vars()
 
 def FindConfiguration(configuration, name):
-  """ Finds a configuration value using it's name. 
+  """ Finds a configuration value using it's name.
       Returns the first configuration with a matching name. Returns None if no
       matching configuration is found. """
   return_value = None
@@ -152,6 +150,6 @@
 
 def ShowErrorPage(error_message):
   print '<html><body>%s</body></html>' % error_message
-  
+
 if __name__ == '__main__':
   main()