[flutter_tools] remove k toggle for canvaskit from web runner (#66273)

The k toggle allows switching between canvaskit and html backend at runtime. unfortunately this causes hot restart to break, since the dart_sdk modules stores state at runtime. The recommendation will be to use cavaskit via dart-defines.

packages/flutter_tools/lib/src/build_runner/resident_web_runner.dart

@@ -799,9 +799,6 @@ class _ResidentWebRunner extends ResidentWebRunner {
     return 0;
   }
 
-  @override
-  bool get supportsCanvasKit => supportsServiceProtocol;
-
   @override
   Future<bool> toggleCanvaskit() async {
     final WebDevFS webDevFS = device.devFS as WebDevFS;

packages/flutter_tools/lib/src/resident_runner.dart

@@ -795,7 +795,6 @@ abstract class ResidentRunner {
   bool get isRunningProfile => debuggingOptions.buildInfo.isProfile;
   bool get isRunningRelease => debuggingOptions.buildInfo.isRelease;
   bool get supportsServiceProtocol => isRunningDebug || isRunningProfile;
-  bool get supportsCanvasKit => false;
   bool get supportsWriteSkSL => supportsServiceProtocol;
   bool get trackWidgetCreation => debuggingOptions.buildInfo.trackWidgetCreation;
 
@@ -1319,9 +1318,6 @@ abstract class ResidentRunner {
         commandHelp.S.print();
         commandHelp.U.print();
       }
-      if (supportsCanvasKit){
-        commandHelp.k.print();
-      }
       if (supportsWriteSkSL) {
         commandHelp.M.print();
       }
@@ -1476,13 +1472,6 @@ class TerminalHandler {
           return true;
         }
         return false;
-      case 'k':
-        if (residentRunner.supportsCanvasKit) {
-          final bool result = await residentRunner.toggleCanvaskit();
-          globals.printStatus('${result ? 'Enabled' : 'Disabled'} CanvasKit');
-          return true;
-        }
-        return false;
       case 'L':
         if (residentRunner.supportsServiceProtocol) {
           await residentRunner.debugDumpLayerTree();

packages/flutter_tools/test/general.shard/resident_runner_test.dart

@@ -1223,8 +1223,6 @@ void main() {
     expect(residentRunner.supportsServiceProtocol, true);
     // isRunningDebug
     expect(residentRunner.isRunningDebug, true);
-    // does not support CanvasKit
-    expect(residentRunner.supportsCanvasKit, false);
     // does support SkSL
     expect(residentRunner.supportsWriteSkSL, true);
     // commands
@@ -1278,8 +1276,6 @@ void main() {
     expect(residentRunner.supportsServiceProtocol, false);
     // isRunningDebug
     expect(residentRunner.isRunningDebug, false);
-    // does not support CanvasKit
-    expect(residentRunner.supportsCanvasKit, false);
     // does support SkSL
     expect(residentRunner.supportsWriteSkSL, false);
     // commands

packages/flutter_tools/test/general.shard/resident_web_runner_test.dart

@@ -759,7 +759,6 @@ void main() {
     final WebAssetServer webAssetServer = WebAssetServer(null, null, null, null, null, null);
     when(mockWebDevFS.webAssetServer).thenReturn(webAssetServer);
 
-    expect(residentWebRunner.supportsCanvasKit, true);
     expect(webAssetServer.canvasKitRendering, false);
 
     final bool toggleResult = await residentWebRunner.toggleCanvaskit();

packages/flutter_tools/test/general.shard/terminal_handler_test.dart

@@ -109,18 +109,6 @@ void main() {
       verify(mockResidentRunner.printHelp(details: true)).called(3);
     });
 
-    testUsingContext('k - toggles CanvasKit rendering and prints results', () async {
-      when(mockResidentRunner.supportsCanvasKit).thenReturn(true);
-      when(mockResidentRunner.toggleCanvaskit())
-        .thenAnswer((Invocation invocation) async {
-          return true;
-        });
-
-      await terminalHandler.processTerminalInput('k');
-
-      verify(mockResidentRunner.toggleCanvaskit()).called(1);
-    });
-
     testUsingContext('i - debugToggleWidgetInspector with service protocol', () async {
       await terminalHandler.processTerminalInput('i');