This adds some plumbing for propagating the status and error code of a

renderer process that went away so that we can tell at the UI level
what happened to the tab: did it crash, or was it killed by the OOM
killer (or some other reason). This is in preparation for implementing
a new UI for when a process is killed by the OOM on ChromeOS which
handles it differently from a crash.

Most of the changes are modifications of the argument list to include
a status and error code for the exited process, but in addition the
following was done:

- Changed the name of DidProcessCrash to GetTerminationStatus.
- Added some new enum values to TerminationStatus enum (and named it)
in process_util.h, so it can be used as the status returned by
WhatHappenedToProcess.
- Improved process_util_unittest to actually test for crashing and
terminated processes on all platforms.
- Added a new notification for renderers that were killed.
- Added error code information to crash notification.
- Added status and error code information to renderer IPC message for
RenderViewGone.
- Added a UMA histogram count for number of renderer kills.

[This change was previously reviewed and LGTM'd:
http://codereview.chromium.org/3386014/show
but due to issues with "git cl push" was never committed to the tree.]

BUG=none
TEST=ran new unit test. Test passes on try servers.

Review URL: http://codereview.chromium.org/3869001

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@63067 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 7 insertions, 5 deletions

diff --git a/chrome/browser/zygote_host_linux.h b/chrome/browser/zygote_host_linux.h
index dd00336..68a72ed 100644
--- a/chrome/browser/zygote_host_linux.h
+++ b/chrome/browser/zygote_host_linux.h
@@ -14,6 +14,7 @@
 #include "base/global_descriptors_posix.h"
 #include "base/lock.h"
 #include "base/process.h"
+#include "base/process_util.h"
 
 template<typename Type>
 struct DefaultSingletonTraits;
@@ -34,17 +35,18 @@ class ZygoteHost {
                      const base::GlobalDescriptors::Mapping& mapping);
   void EnsureProcessTerminated(pid_t process);
 
-  // Get the termination status (exit code) of the process and return true if
-  // the status indicates the process crashed. |child_exited| is set to true
-  // iff the child process has terminated. (|child_exited| may be NULL.)
-  bool DidProcessCrash(base::ProcessHandle handle, bool* child_exited);
+  // Get the termination status (and, optionally, the exit code) of
+  // the process. |exit_code| is set to the exit code of the child
+  // process. (|exit_code| may be NULL.)
+  base::TerminationStatus GetTerminationStatus(base::ProcessHandle handle,
+                                                int* exit_code);
 
   // These are the command codes used on the wire between the browser and the
   // zygote.
   enum {
     kCmdFork = 0,             // Fork off a new renderer.
     kCmdReap = 1,             // Reap a renderer child.
-    kCmdDidProcessCrash = 2,  // Check if child process crashed.
+    kCmdGetTerminationStatus = 2,  // Check what happend to a child process.
     kCmdGetSandboxStatus = 3, // Read a bitmask of kSandbox*
   };