[Telemetry] Always close browser backend in Close()

telemetry/telemetry/internal/browser/browser.py

 # Copyright 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import logging
 import sys
 
 from catapult_base import cloud_storage  # pylint: disable=import-error
 
 from telemetry.core import exceptions
@@ skipping 204 matching lines @@
     cpu_timestamp = self._platform_backend.GetCpuTimestamp()
     for process_type in result:
       # Skip any process_types that are empty
       if not len(result[process_type]):
         continue
       result[process_type].update(cpu_timestamp)
     return result
 
   def Close(self):
     """Closes this browser."""
-    if self._browser_backend.IsBrowserRunning():
-      self._platform_backend.WillCloseBrowser(self, self._browser_backend)
+    try:
+      if self._browser_backend.IsBrowserRunning():
+        self._platform_backend.WillCloseBrowser(self, self._browser_backend)
 
-    self._browser_backend.profiling_controller_backend.WillCloseBrowser()
-    if self._browser_backend.supports_uploading_logs:
-      try:
-        self._browser_backend.UploadLogsToCloudStorage()
-      except cloud_storage.CloudStorageError as e:
-        logging.error('Cannot upload browser log: %s' % str(e))
-    self._browser_backend.Close()
-    self.credentials = None
+      self._browser_backend.profiling_controller_backend.WillCloseBrowser()
+      if self._browser_backend.supports_uploading_logs:
+        try:
+          self._browser_backend.UploadLogsToCloudStorage()
+        except cloud_storage.CloudStorageError as e:
+          logging.error('Cannot upload browser log: %s' % str(e))
+    finally:
+      self._browser_backend.Close()
+      self.credentials = None
 
 
   def GetStandardOutput(self):
     return self._browser_backend.GetStandardOutput()
 
   def GetStackTrace(self):
     return self._browser_backend.GetStackTrace()
 
   @property
   def supports_system_info(self):
@@ skipping 31 matching lines @@
   def supports_cpu_metrics(self):
     return self._browser_backend.supports_cpu_metrics
 
   @property
   def supports_memory_metrics(self):
     return self._browser_backend.supports_memory_metrics
 
   @property
   def supports_power_metrics(self):
     return self._browser_backend.supports_power_metrics