Apply normalization to TimePickerThemeData.inputDecorationTheme (#171584)

## Description

This PR is similar to what was done for `DatePickerThemeData` in
https://github.com/flutter/flutter/pull/168981.
It changes `TimePickerThemeData.inputDecorationTheme` type to
`InputDecorationThemeData` (instead of `InputDecorationTheme`) and uses
Object? for the corresponding constructor parameter.

## Tests

Adds 1 test
https://dart.googlesource.com/external/github.com/flutter/flutter/+/41c21bbf927dfbc1fc1f6846da3797808a4fac34

DEPS

diff --git a/DEPS b/DEPS
index 6cada5d..a0374e1 100644
--- a/DEPS
+++ b/DEPS
@@ -231,7 +231,7 @@
 deps = {
   'flutter/engine/src/flutter/third_party/dart': Var('dart_git') + '/sdk' + '@' + '1a39e3530fb603323395b8dda9c24d1217b70d13',
 
-  'flutter': Var('flutter_git') + '/mirrors/flutter' + '@' + '50407af0a1ea294a1d65585ee0c428fc3b8adba7',
+  'flutter': Var('flutter_git') + '/mirrors/flutter' + '@' + '41c21bbf927dfbc1fc1f6846da3797808a4fac34',
 
   'flutter/engine/src/flutter/third_party/depot_tools':
   Var('chromium_git') + '/chromium/tools/depot_tools.git' + '@' + '580b4ff3f5cd0dcaa2eacda28cefe0f45320e8f7',

commits.json

diff --git a/commits.json b/commits.json
index 49efafa..e436271 100644
--- a/commits.json
+++ b/commits.json
@@ -1,4 +1,4 @@
 {
-  "flutter":"50407af0a1ea294a1d65585ee0c428fc3b8adba7",
+  "flutter":"41c21bbf927dfbc1fc1f6846da3797808a4fac34",
   "flutter/engine/src/flutter/third_party/dart":"1a39e3530fb603323395b8dda9c24d1217b70d13"
 }
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