Download webstore CRXs into separate directory.

chrome/browser/extensions/api/webstore_private/webstore_private_api.cc

Index: chrome/browser/extensions/api/webstore_private/webstore_private_api.cc
diff --git a/chrome/browser/extensions/api/webstore_private/webstore_private_api.cc b/chrome/browser/extensions/api/webstore_private/webstore_private_api.cc
index 3c664aae23f8565efe33f515e32e4b7570a4928c..f0bc02173b7d473a53279e38e649c95e2b8c83a3 100644
--- a/chrome/browser/extensions/api/webstore_private/webstore_private_api.cc
+++ b/chrome/browser/extensions/api/webstore_private/webstore_private_api.cc
@@ -8,6 +8,7 @@
 #include "base/command_line.h"
 #include "base/lazy_instance.h"
 #include "base/memory/scoped_vector.h"
+#include "base/metrics/histogram.h"
 #include "base/prefs/pref_service.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
@@ -183,6 +184,10 @@ void SetWebstoreLogin(Profile* profile, const std::string& login) {
   profile->GetPrefs()->SetString(kWebstoreLogin, login);
 }
 
+void RecordWebstoreExtensionInstallResult(bool success) {
+  UMA_HISTOGRAM_BOOLEAN("Webstore.ExtensionInstallResult", success);
+}
+
 }  // namespace
 
 // static
@@ -577,6 +582,8 @@ void WebstorePrivateCompleteInstallFunction::OnExtensionInstallSuccess(
   g_pending_installs.Get().EraseInstall(GetProfile(), id);
   SendResponse(true);
 
+  RecordWebstoreExtensionInstallResult(true);
+
   // Matches the AddRef in RunImpl().
   Release();
 }
@@ -595,6 +602,8 @@ void WebstorePrivateCompleteInstallFunction::OnExtensionInstallFailure(
   g_pending_installs.Get().EraseInstall(GetProfile(), id);
   SendResponse(false);
 
+  RecordWebstoreExtensionInstallResult(false);
+
   // Matches the AddRef in RunImpl().
   Release();
 }