Add histograms to compare GetVersionEx() with VerQueryValue() of kernel32

chrome/browser/metrics/chrome_browser_main_extra_parts_metrics.cc

Index: chrome/browser/metrics/chrome_browser_main_extra_parts_metrics.cc
diff --git a/chrome/browser/metrics/chrome_browser_main_extra_parts_metrics.cc b/chrome/browser/metrics/chrome_browser_main_extra_parts_metrics.cc
index 11b1c174972f5628714a5ad12299ca6ff5104d06..bf35712b3427527a7222c155eddfbf9cec203658 100644
--- a/chrome/browser/metrics/chrome_browser_main_extra_parts_metrics.cc
+++ b/chrome/browser/metrics/chrome_browser_main_extra_parts_metrics.cc
@@ -51,6 +51,7 @@
 #endif  // defined(USE_OZONE) || defined(USE_X11)
 
 #if defined(OS_WIN)
+#include "base/win/windows_version.h"
 #include "chrome/installer/util/google_update_settings.h"
 #endif  // defined(OS_WIN)
 
@@ -140,6 +141,17 @@ void RecordMicroArchitectureStats() {
 void RecordStartupMetricsOnBlockingPool() {
 #if defined(OS_WIN)
   GoogleUpdateSettings::RecordChromeUpdatePolicyHistograms();
+
+  UMA_HISTOGRAM_ENUMERATION("Windows.GetVersionExVersion",
+                            base::win::OSInfo::GetInstance()->version(),
+                            base::win::VERSION_WIN_LAST);
+  UMA_HISTOGRAM_ENUMERATION("Windows.Kernel32Version",
+                            base::win::OSInfo::GetInstance()->Kernel32Version(),
+                            base::win::VERSION_WIN_LAST);
+  UMA_HISTOGRAM_BOOLEAN(
+      "Windows.InCompatibilityMode",
+      base::win::OSInfo::GetInstance()->version() !=
+          base::win::OSInfo::GetInstance()->Kernel32Version());

[Alexei Svitkine (slow), 2016/03/11 20:16:51]

Nit: make a local var for base::win::OSInfo::GetInstance() since you use it 4
times above, so it will make the code a bit more concise.

[scottmg, 2016/03/11 22:44:26]

Done.

 #endif  // defined(OS_WIN)
 
 #if defined(OS_MACOSX)