Added histograms on process singleton create when remote process exists and we cannot notify it

chrome/browser/process_singleton.h

Index: chrome/browser/process_singleton.h
diff --git a/chrome/browser/process_singleton.h b/chrome/browser/process_singleton.h
index 96a9bf65f42d2cfab301a10573b25739e7e05a4e..863b9e0955e01e035323b76356a46abf4218bf52 100644
--- a/chrome/browser/process_singleton.h
+++ b/chrome/browser/process_singleton.h
@@ -49,6 +49,34 @@ class CommandLine;
 
 class ProcessSingleton : public base::NonThreadSafe {
  public:
+  // Used to send the reason of remote hang process termination as histogram.
+  enum RemoteHungProcessTerminateReason {
+    USER_ACCEPTED_TERMINATION,
+    NO_VISIBLE_WINDOW_FOUND,
+    NOTIFY_ATTEMPTS_EXCEEDED,
+    SOCKET_WRITE_FAILED,
+    SOCKET_READ_FAILED,
+    MAX_REMOTE_HUNG_PROCESS_TERMINATE_REASON

[gab, 2017/05/10 15:16:50]

This isn't a MAX, it's a COUNT or maybe END (since ends in C++'s are usually
past-the-end).

[Alexey Seren, 2017/05/11 13:42:05]

Acknowledged.

REMOTE_HUNG_PROCESS_TERMINATE_REASON_COUNT will be more appropriate.

+  };
+
+  // Used to send the result of interaction with remote process as histograms in
+  // case when remote process influences on start.
+  enum RemoteProcessInteractionResult {
+    TERMINATE_SUCCEEDED,
+    TERMINATE_FAILED,
+    TERMINATE_WAIT_TIMEOUT,
+    TERMINATE_NOT_ENOUGH_PERMISSIONS,
+    REMOTE_PROCESS_SHUTTING_DOWN,
+    PROFILE_UNLOCKED,
+    REMOTE_PROCESS_NOT_FOUND,
+    FAILED_TO_EXTRACT_PID,
+    INVALID_LOCK_FILE,
+    ORPHANED_LOCK_FILE,
+    SAME_BROWSER_INSTANCE,
+    REMOTE_PROCESS_NOTIFY_FAILED,
+    MAX_HUNG_REMOTE_PROCESS_ACTION
+  };
+
   // Logged as histograms, do not modify these values.
   enum NotifyResult {
     PROCESS_NONE = 0,