Telemetry: Profilers ignore disappearing processes.

tools/telemetry/telemetry/core/platform/profiler/__init__.py

Index: tools/telemetry/telemetry/core/platform/profiler/__init__.py
diff --git a/tools/telemetry/telemetry/core/platform/profiler/__init__.py b/tools/telemetry/telemetry/core/platform/profiler/__init__.py
index 58febc9182e4b62d44bb6cfed54d5c620d13001a..806229e907efcf5167414529a0a951cd9a5b9cc7 100644
--- a/tools/telemetry/telemetry/core/platform/profiler/__init__.py
+++ b/tools/telemetry/telemetry/core/platform/profiler/__init__.py
@@ -4,6 +4,8 @@
 
 import collections
 
+from telemetry.core import exceptions
+
 class Profiler(object):
   """A sampling profiler provided by the platform.
 
@@ -49,12 +51,16 @@ class Profiler(object):
     process_name_counts = collections.defaultdict(int)
     process_output_file_map = {}
     for pid in all_pids:
-      cmd_line = self._platform_backend.GetCommandLine(pid)
-      process_name = self._browser_backend.GetProcessName(cmd_line)
-      output_file = '%s.%s%s' % (self._output_path, process_name,
-                                 process_name_counts[process_name])
-      process_name_counts[process_name] += 1
-      process_output_file_map[pid] = output_file
+      try:
+        cmd_line = self._platform_backend.GetCommandLine(pid)
+        process_name = self._browser_backend.GetProcessName(cmd_line)
+        output_file = '%s.%s%s' % (self._output_path, process_name,
+                                   process_name_counts[process_name])
+        process_name_counts[process_name] += 1
+        process_output_file_map[pid] = output_file
+      except exceptions.ProcessGoneException:
+        # Ignore processes that disappeared since calling GetChildPids().
+        continue
     return process_output_file_map
 
   def CollectProfile(self):