Minor Dart 2.0 tweaks for Intl and related packages

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=170079157
diff --git a/lib/src/intl/number_format.dart b/lib/src/intl/number_format.dart
index df4140a..bf7a388 100644
--- a/lib/src/intl/number_format.dart
+++ b/lib/src/intl/number_format.dart
@@ -855,10 +855,6 @@
     _buffer.writeCharCode(x + _zeroOffset);
   }
 
-  void _padEmpty(int howMany) {
-    _buffer.write(symbols.ZERO_DIGIT * howMany);
-  }
-
   void _pad(int numberOfDigits, String basic) {
     if (_zeroOffset == 0) {
       _buffer.write(basic.padLeft(numberOfDigits, '0'));
diff --git a/test/date_time_format_test_core.dart b/test/date_time_format_test_core.dart
index 55519de..8e347d3 100644
--- a/test/date_time_format_test_core.dart
+++ b/test/date_time_format_test_core.dart
@@ -387,7 +387,7 @@
   /// [leapDay], otherwise pass 0.
   Map<int, DateTime> generateDates(int year, int leapDay) =>
       new Iterable.generate(365 + leapDay, (n) => n + 1)
-          .map/*<DateTime>*/((day) {
+          .map((day) {
             var result = new DateTime(year, 1, day);
             // TODO(alanknight): This is a workaround for dartbug.com/15560.
             if (result.toUtc() == result) result = new DateTime(year, 1, day);
diff --git a/test/find_default_locale_browser_test.dart b/test/find_default_locale_browser_test.dart
index 8aac05a..fbbdcd1 100644
--- a/test/find_default_locale_browser_test.dart
+++ b/test/find_default_locale_browser_test.dart
@@ -15,7 +15,7 @@
     // should find a way to force the system locale before the test is run
     // and then verify that it's actually the correct value.
     Intl.systemLocale = 'xx_YY';
-    ThenArgument callback = expectAsync(verifyLocale) as ThenArgument;
+    ThenArgument callback = expectAsync1(verifyLocale) as ThenArgument;
     findSystemLocale().then(callback);
   });
 }
diff --git a/test/find_default_locale_standalone_test.dart b/test/find_default_locale_standalone_test.dart
index 10d5f27..033ad46 100644
--- a/test/find_default_locale_standalone_test.dart
+++ b/test/find_default_locale_standalone_test.dart
@@ -14,7 +14,7 @@
     // and then verify that it's actually the correct value.
     // We have no way of getting this reliably for Windows, so it will fail.
     Intl.systemLocale = "xx_YY";
-    var callback = expectAsync(verifyLocale) as ThenArgument;
+    var callback = expectAsync1(verifyLocale) as ThenArgument;
     findSystemLocale().then(callback);
   });
 }
diff --git a/test/number_closure_test.dart b/test/number_closure_test.dart
index af43bda..13431fa 100644
--- a/test/number_closure_test.dart
+++ b/test/number_closure_test.dart
@@ -382,8 +382,7 @@
 typedef void TimerArgument();
 testLocaleSwitchAsync() {
   Intl.withLocale("fr", () {
-    new Timer(new Duration(milliseconds: 10),
-        expectAsync(verifyFrenchLocale) as TimerArgument);
+    new Timer(new Duration(milliseconds: 10), expectAsync0(verifyFrenchLocale));
   });
   // Verify that things running outside the zone still get en_US.
   testStandardFormat();
diff --git a/test/number_format_compact_test.dart b/test/number_format_compact_test.dart
index 607dc20..096392f 100644
--- a/test/number_format_compact_test.dart
+++ b/test/number_format_compact_test.dart
@@ -11,7 +11,7 @@
 
 /// A place to put a case that's causing a problem and have it run first when
 /// debugging
-var interestingCases = {
+var interestingCases = <String, List<List<String>>>{
 //  "mn" : [["4321", "4.32M", "whatever"]]
 };
 
diff --git a/test/number_format_test.dart b/test/number_format_test.dart
index d40a5c7..5539fd5 100644
--- a/test/number_format_test.dart
+++ b/test/number_format_test.dart
@@ -300,10 +300,10 @@
 
 testCurrencySymbolsFor(expected, formats, name) {
   var amount = 1000000.32;
-  new Map.fromIterables(expected, formats)
+  new Map<Object, NumberFormat>.fromIterables(expected, formats)
       .forEach((expected, NumberFormat format) {
     test("Test $name ${format.currencyName}", () {
-      // We have to allow for currencies with different fraction digits, e.g. CRC.
+      // Allow for currencies with different fraction digits, e.g. CRC.
       var maxDigits = format.maximumFractionDigits;
       var rounded = maxDigits == 0 ? amount.round() : amount;
       var fractionDigits = (amount - rounded) < 0.00001 ? '.32' : '';