SDK fixes

tool/input_sdk/patch/convert_patch.dart

Index: tool/input_sdk/patch/convert_patch.dart
diff --git a/tool/input_sdk/patch/convert_patch.dart b/tool/input_sdk/patch/convert_patch.dart
index f7eb2bda795a62467045c9a5c99a5fb9273ec77f..f851bce06730c15892c8693c1332b6727b80f2f8 100644
--- a/tool/input_sdk/patch/convert_patch.dart
+++ b/tool/input_sdk/patch/convert_patch.dart
@@ -140,7 +140,7 @@ class _JsonMap implements LinkedHashMap {
 
   _JsonMap(this._original);
 
-  operator[](key) {
+  operator[](Object key) {
     if (_isUpgraded) {
       return _upgradedMap[key];
     } else if (key is !String) {
@@ -190,7 +190,7 @@ class _JsonMap implements LinkedHashMap {
     });
   }
 
-  bool containsValue(value) {
+  bool containsValue(Object value) {
     if (_isUpgraded) return _upgradedMap.containsValue(value);
     List<String> keys = _computeKeys();
     for (int i = 0; i < keys.length; i++) {
@@ -200,7 +200,7 @@ class _JsonMap implements LinkedHashMap {
     return false;
   }
 
-  bool containsKey(key) {
+  bool containsKey(Object key) {
     if (_isUpgraded) return _upgradedMap.containsKey(key);
     if (key is !String) return false;
     return _hasProperty(_original, key);