Restore the chrome watcher pending relocation

chrome/app/main_dll_loader_win.cc

Index: chrome/app/main_dll_loader_win.cc
diff --git a/chrome/app/main_dll_loader_win.cc b/chrome/app/main_dll_loader_win.cc
index 66a3034e91f9b728fc09f03b038b62dbb00c231b..e59ae115ba9cb97627abc2dac67513b336dc5697 100644
--- a/chrome/app/main_dll_loader_win.cc
+++ b/chrome/app/main_dll_loader_win.cc
@@ -203,6 +203,26 @@ void ChromeDllLoader::OnBeforeLaunch(const std::string& process_type,
                                      const base::FilePath& dll_path) {
   if (process_type.empty()) {
     RecordDidRun(dll_path);
+
+    // Get the function that determines whether uploads are enabled.
+    typedef bool (*GetUploadsEnabledFunction)(void);
+    static GetUploadsEnabledFunction get_uploads_enabled = nullptr;

[Sigurður Ásgeirsson, 2016/09/01 15:30:36]

You may want to check this with chrome-metrics folks, but I think gating
functionality on consent is strongly discouraged.

[Alexei Svitkine (slow), 2016/09/01 15:40:26]

Agreed. If you're just doing this to "save extra work since metrics won't be
reported to anywhere", please don't. We don't want consented users to have lower
performance than non consented users, since this discourages users from giving
consent.

Happy to discuss in more detail if the case is different from the above.

[manzagop (departed), 2016/09/01 16:02:49]

Done.

+    if (!get_uploads_enabled) {
+      get_uploads_enabled =
+          reinterpret_cast<GetUploadsEnabledFunction>(GetProcAddress(
+              GetModuleHandle(chrome::kChromeElfDllName), "GetUploadsEnabled"));
+      CHECK(get_uploads_enabled);
+    }
+
+    // Launch the watcher process if stats collection consent has been granted.
+    if (get_uploads_enabled()) {
+      base::FilePath exe_path;
+      if (PathService::Get(base::FILE_EXE, &exe_path)) {
+        chrome_watcher_client_.reset(new ChromeWatcherClient(
+            base::Bind(&GenerateChromeWatcherCommandLine, exe_path)));
+        chrome_watcher_client_->LaunchWatcher();
+      }
+    }
   } else {
     // Set non-browser processes up to be killed by the system after the browser
     // goes away. The browser uses the default shutdown order, which is 0x280.