Persist setup metrics and have Chrome report them during UMA upload.

chrome/installer/util/util_constants.h

Index: chrome/installer/util/util_constants.h
diff --git a/chrome/installer/util/util_constants.h b/chrome/installer/util/util_constants.h
index c7312399377c2cc012851c1ccb5f9fc33691760f..b83be739432c7da452be594a35a2a95a4224e298 100644
--- a/chrome/installer/util/util_constants.h
+++ b/chrome/installer/util/util_constants.h
@@ -253,6 +253,10 @@ const int kBsdiffErrorOffset = 600;
 extern const char kCourgette[];
 extern const char kBsdiff[];
 
+// Name of the allocator (and associated file) for storing histograms to be
+// reported by Chrome during its next upload.
+extern const char kSetupHistogramAllocatorName[];
+
 }  // namespace installer
 
 #endif  // CHROME_INSTALLER_UTIL_UTIL_CONSTANTS_H_