Use static_cast instead of reinterpret_cast for downcasting

static_cast is better suited for downcasting since it can check that the
types are related.

/chrome/browser/ui/views/webauthn
This CL was uploaded by git cl split.

R=nsatragno@chromium.org

Change-Id: I0d2cf195336da3a9bcb34465d2e5e8e144807ad6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2435881
Auto-Submit: Kevin McNee <mcnee@chromium.org>
Reviewed-by: Nina Satragno <nsatragno@chromium.org>
Commit-Queue: Nina Satragno <nsatragno@chromium.org>
Cr-Commit-Position: refs/heads/master@{#811336}

chrome/browser/ui/views/webauthn/authenticator_qr_sheet_view.cc

@@ -231,7 +231,7 @@ class AuthenticatorQRViewCentered : public views::View {
 AuthenticatorQRSheetView::AuthenticatorQRSheetView(
     std::unique_ptr<AuthenticatorQRSheetModel> sheet_model)
     : AuthenticatorRequestSheetView(std::move(sheet_model)),
-      qr_generator_key_(reinterpret_cast<AuthenticatorQRSheetModel*>(model())
+      qr_generator_key_(static_cast<AuthenticatorQRSheetModel*>(model())
                             ->dialog_model()
                             ->qr_generator_key()) {}