Fix lint errors to enable stricter PyLint rules

These fixes are needed to avoid errors after submitting
https://codereview.webrtc.org/2737963003

BUG=webrtc:7303
NOTRY=True

Review-Url: https://codereview.webrtc.org/2812273002
Cr-Commit-Position: refs/heads/master@{#17679}
diff --git a/webrtc/tools/video_analysis_test.py b/webrtc/tools/video_analysis_test.py
index 483632b..e0c0f4b 100755
--- a/webrtc/tools/video_analysis_test.py
+++ b/webrtc/tools/video_analysis_test.py
@@ -13,28 +13,28 @@
 
 
 class RunVideoAnalysisTest(unittest.TestCase):
-  def setGlobPath(self, path1, path2):
+  def SetGlobPath(self, path1, path2):
     self.path1 = path1
     self.path2 = path2
 
   def setUp(self):
     self.path1 = ''
     self.path2 = ''
-    self.requestNbr = 1
+    self.request_nbr = 1
 
-    def glob_mock(string):
+    def GlobMock(string):
       # Eat incoming string.
       del string
-      if self.requestNbr == 1:
-        self.requestNbr += 1
+      if self.request_nbr == 1:
+        self.request_nbr += 1
         return self.path1
       else:
-        self.requestNbr = 1
+        self.request_nbr = 1
         return self.path2
 
     # Override the glob function with our own that returns a string set by the
     # test.
-    glob.glob = glob_mock
+    glob.glob = GlobMock
 
   # Verifies that the correct USB id is returned.
   def testFindUSBPortForV4lDevices(self):
@@ -42,7 +42,7 @@
                    'video4linux/video0')
     short_path2 = ('/sys/bus/usb/devices/usb1/1-1/driver/4-3/4-3:1.0/'
                    'video4linux/video1')
-    self.setGlobPath(short_path1, short_path2)
+    self.SetGlobPath(short_path1, short_path2)
     short_usb_ids = ['4-4', '4-3']
     self.assertEqual(FindUsbPortForV4lDevices('video0', 'video1'),
                      short_usb_ids)
@@ -51,16 +51,16 @@
                   'video4linux/video0')
     long_path2 = ('/sys/bus/usb/devices/usb1/1-1/driver/3-2/3-2.1:1.0/'
                   'video4linux/video1')
-    self.setGlobPath(long_path1, long_path2)
+    self.SetGlobPath(long_path1, long_path2)
     long_usb_ids = ['3-3.1', '3-2.1']
     self.assertEqual(FindUsbPortForV4lDevices('video0', 'video1'), long_usb_ids)
 
 
   def testFindUSBPortForV4lDevicesNoDevice(self):
-    noDeviceFound = ('')
-    V4lDevice = ('/sys/bus/usb/devices/usb1/1-1/driver/3-2/3-2.1:1.0/'
+    no_device_found = ('')
+    v4l_device = ('/sys/bus/usb/devices/usb1/1-1/driver/3-2/3-2.1:1.0/'
                   'video4linux/video1')
-    self.setGlobPath(noDeviceFound, V4lDevice)
+    self.SetGlobPath(no_device_found, v4l_device)
     empty_list = []
     self.assertEqual(FindUsbPortForV4lDevices('video0', 'video1'), empty_list)