upgrade flutter to 3.22.2 and fix errors (#13)

Author: ClaireDavis

charts_common/lib/src/chart/bar/base_bar_renderer.dart

@@ -808,7 +808,7 @@ class _ReversedSeriesIterable<S extends ImmutableSeries<Object?>>
 /// order it was passed in for the grouping, but the series is flipped so that
 /// the first series of that category is on the top of the stack.
 class _ReversedSeriesIterator<S extends ImmutableSeries<Object?>>
-    extends Iterator<S> {
+    implements Iterator<S> {
   final List<S> _list;
   final _visitIndex = <int>[];
   int? _current;

charts_common/lib/src/chart/cartesian/axis/time/time_stepper.dart

@@ -45,7 +45,7 @@ abstract class TimeStepper {
 
 /// Iterator with a reset function that can be used multiple times to avoid
 /// object instantiation during the Android layout/draw phases.
-abstract class TimeStepIterator extends Iterator<DateTime> {
+abstract class TimeStepIterator implements Iterator<DateTime> {
   /// Reset the iterator and set the tickIncrement to the specified value.
   ///
   /// This method is provided so that the same iterator instance can be used for

charts_common/pubspec.yaml

@@ -5,11 +5,11 @@ author: Charts Team <[email protected]>
 homepage: https://github.com/google/charts
 
 environment:
-  sdk: '>=2.12.0 <3.0.0'
+  sdk: ">=3.4.3 <4.0.0"
 
 dependencies:
   collection: ^1.14.5
-  intl: ">=0.15.2 <= 0.19.0"  
+  intl: ">=0.15.2 <= 0.19.0"
   logging: any
   meta: ^1.1.1
   vector_math: ^2.0.8

charts_flutter/lib/src/behaviors/legend/legend_entry_layout.dart

@@ -131,7 +131,7 @@ class SimpleLegendEntryLayout implements LegendEntryLayout {
         : null;
     if (isHidden) {
       // Use a default color for hidden legend entries if none is provided.
-      color ??= Theme.of(context).textTheme.bodyText2!.color;
+      color ??= Theme.of(context).textTheme.bodyMedium!.color;
       color = color!.withOpacity(0.26);
     }
 

charts_flutter/pubspec.yaml

@@ -5,7 +5,7 @@ author: Charts Team <[email protected]>
 homepage: https://github.com/google/charts
 
 environment:
-  sdk: '>=3.0.2 <4.0.0'
+  sdk: ">=3.4.3 <4.0.0"
 
 dependencies:
   # Pointing this to a local path allows for pointing to the latest code