Remove OneClickSigninHelper since it is no longer used.

chrome/browser/ui/cocoa/one_click_signin_view_controller.mm

Index: chrome/browser/ui/cocoa/one_click_signin_view_controller.mm
diff --git a/chrome/browser/ui/cocoa/one_click_signin_view_controller.mm b/chrome/browser/ui/cocoa/one_click_signin_view_controller.mm
index 50e2931b8d6636fc51cb7af8473a81035c36b427..6ecd11ee8de8b01fd67016cc2f29f1a780c2beab 100644
--- a/chrome/browser/ui/cocoa/one_click_signin_view_controller.mm
+++ b/chrome/browser/ui/cocoa/one_click_signin_view_controller.mm
@@ -8,7 +8,6 @@
 #include "base/logging.h"
 #include "base/mac/bundle_locations.h"
 #import "chrome/browser/ui/chrome_style.h"
-#include "chrome/browser/ui/sync/one_click_signin_helper.h"
 #include "chrome/common/url_constants.h"
 #include "chrome/grit/chromium_strings.h"
 #include "chrome/grit/generated_resources.h"
@@ -78,7 +77,7 @@ void ShiftOriginY(NSView* view, CGFloat amount) {
 
 - (IBAction)ok:(id)sender {
   if (isSyncDialog_) {
-    OneClickSigninHelper::LogConfirmHistogramValue(
+    signin_metrics::LogSigninConfirmHistogramValue(
         clickedLearnMore_ ?
             signin_metrics::HISTOGRAM_CONFIRM_LEARN_MORE_OK :
             signin_metrics::HISTOGRAM_CONFIRM_OK);
@@ -91,7 +90,7 @@ void ShiftOriginY(NSView* view, CGFloat amount) {
 
 - (IBAction)onClickUndo:(id)sender {
   if (isSyncDialog_) {
-    OneClickSigninHelper::LogConfirmHistogramValue(
+    signin_metrics::LogSigninConfirmHistogramValue(
         clickedLearnMore_ ?
             signin_metrics::HISTOGRAM_CONFIRM_LEARN_MORE_UNDO :
             signin_metrics::HISTOGRAM_CONFIRM_UNDO);
@@ -104,7 +103,7 @@ void ShiftOriginY(NSView* view, CGFloat amount) {
 
 - (IBAction)onClickAdvancedLink:(id)sender {
   if (isSyncDialog_) {
-    OneClickSigninHelper::LogConfirmHistogramValue(
+    signin_metrics::LogSigninConfirmHistogramValue(
         clickedLearnMore_ ?
             signin_metrics::HISTOGRAM_CONFIRM_LEARN_MORE_ADVANCED :
             signin_metrics::HISTOGRAM_CONFIRM_ADVANCED);
@@ -123,7 +122,7 @@ void ShiftOriginY(NSView* view, CGFloat amount) {
 
 - (IBAction)onClickClose:(id)sender {
   if (isSyncDialog_) {
-    OneClickSigninHelper::LogConfirmHistogramValue(
+    signin_metrics::LogSigninConfirmHistogramValue(
         clickedLearnMore_ ?
             signin_metrics::HISTOGRAM_CONFIRM_LEARN_MORE_CLOSE :
             signin_metrics::HISTOGRAM_CONFIRM_CLOSE);
@@ -211,7 +210,7 @@ void ShiftOriginY(NSView* view, CGFloat amount) {
                                       delta:delta];
 
   if (isSyncDialog_) {
-    OneClickSigninHelper::LogConfirmHistogramValue(
+    signin_metrics::LogSigninConfirmHistogramValue(
         signin_metrics::HISTOGRAM_CONFIRM_SHOWN);
   }
 }
@@ -287,7 +286,7 @@ void ShiftOriginY(NSView* view, CGFloat amount) {
   if (isSyncDialog_ && !clickedLearnMore_) {
     clickedLearnMore_ = YES;
 
-    OneClickSigninHelper::LogConfirmHistogramValue(
+    signin_metrics::LogSigninConfirmHistogramValue(
         signin_metrics::HISTOGRAM_CONFIRM_LEARN_MORE);
   }
   WindowOpenDisposition location = isSyncDialog_ ?