Enable AutoResize for Constrained Web Dialogs for Mac.

chrome/browser/ui/cocoa/ssl_client_certificate_selector_cocoa.mm

Index: chrome/browser/ui/cocoa/ssl_client_certificate_selector_cocoa.mm
diff --git a/chrome/browser/ui/cocoa/ssl_client_certificate_selector_cocoa.mm b/chrome/browser/ui/cocoa/ssl_client_certificate_selector_cocoa.mm
index 6e2703d34d4092a360d92cb0cae1b6cbc5c1ded9..f634d1103d2bc59ec1fc5aa3f6f1933a9c4b27c3 100644
--- a/chrome/browser/ui/cocoa/ssl_client_certificate_selector_cocoa.mm
+++ b/chrome/browser/ui/cocoa/ssl_client_certificate_selector_cocoa.mm
@@ -176,7 +176,7 @@ void ShowSSLClientCertificateSelector(
   }
 
   constrainedWindow_.reset(
-      new ConstrainedWindowMac(observer_.get(), webContents, self));
+      CreateAndShowWebModalDialogMac(observer_.get(), webContents, self));
   observer_->StartObserving();
 }
 
@@ -256,6 +256,10 @@ void ShowSSLClientCertificateSelector(
   // NOOP
 }
 
+- (void)resizeWithNewSize:(NSSize)size {
+  // NOOP
+}
+
 - (NSWindow*)sheetWindow {
   return panel_;
 }