Treat PPAPI disconnect as a crash for plugin metrics.

chrome/browser/metrics/plugin_metrics_provider_unittest.cc

 // Copyright 2014 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.
 
 #include "chrome/browser/metrics/plugin_metrics_provider.h"
 
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/prefs/pref_service.h"
@@ skipping 152 matching lines @@
                                          "1.5", true));
   provider.SetPluginsForTesting(plugins);
   metrics::SystemProfileProto system_profile;
   provider.ProvideSystemProfileMetrics(&system_profile);
 
   // Increase number of created instances which should also start a delayed
   // task.
   content::ChildProcessData child_process_data(content::PROCESS_TYPE_PLUGIN);
   child_process_data.name = base::UTF8ToUTF16("p1");
   provider.BrowserChildProcessInstanceCreated(child_process_data);
+  provider.BrowserChildProcessInstanceCreated(child_process_data);
+
+  provider.BrowserChildProcessCrashed(child_process_data, 1);
+  provider.BrowserChildProcessHostDisconnected(child_process_data);
+  provider.BrowserChildProcessCrashed(child_process_data, 2);

[Alexei Svitkine (slow), 2015/08/03 16:57:07]

Hmm, is this a realistic scenario? Seems like if there's only two instances and
we get those 3 messages, we'd be double counting crashes? e.g. if an instance
both crashed and disconnected presumably we only want to count it once?

I mean, maybe that's not a thing that would happen in practice. But in that
case, the test shouldn't be simulating it. But if it is a thing might actually
happen in practice, then maybe the class needs extra logic to de-dup them (e.g.
by having the disconnect message take the instance id and keeping track of which
ones already crashed?).

 
   // Call ProvideStabilityMetrics to check that it will force pending tasks to
   // be executed immediately.
   provider.ProvideStabilityMetrics(&system_profile);
 
   // Check current number of instances created.
   const metrics::SystemProfileProto_Stability& stability =
       system_profile.stability();
-  EXPECT_EQ(1, stability.plugin_stability(0).instance_count());
+  EXPECT_EQ(2, stability.plugin_stability(0).instance_count());
+  EXPECT_EQ(3, stability.plugin_stability(0).crash_count());
 }