Merge Crashpad to the 42.0.2311 branch

chrome/common/chrome_switches.cc

Index: chrome/common/chrome_switches.cc
diff --git a/chrome/common/chrome_switches.cc b/chrome/common/chrome_switches.cc
index 50ad6174968688b036b15146afcf270779e85419..c60ebfda6c18909318a2555bf50993c0c40a3731 100644
--- a/chrome/common/chrome_switches.cc
+++ b/chrome/common/chrome_switches.cc
@@ -1282,6 +1282,11 @@ const char kDisableSystemFullscreenForTesting[] =
 // chrome/browser/mac/relauncher.h.
 const char kRelauncherProcess[]             = "relauncher";
 
+// This is how the metrics client ID is passed from the browser process to its
+// children. With Crashpad, the metrics client ID is distinct from the crash
+// client ID.
+const char kMetricsClientID[]               = "metrics-client-id";
+
 #endif
 
 // Use bubbles for content permissions requests instead of infobars.