Deprecate M2 curves (#134417)

These have 1:1 replacements with a new name, introduced in
#129942

Land after flutter/packages#4898

Part of #116525

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packages/flutter/lib/fix_data/fix_material/fix_material.yaml

@@ -897,9 +897,9 @@ transforms:
         oldName: 'showTrackOnHover'
         newName: 'trackVisibility'
 
-  # Changes made in https://github.com/flutter/flutter/pull/129942
+  # Changes made in https://github.com/flutter/flutter/pull/134417
   - title: "Migrate to 'Easing.legacy'"
-    date: 2023-07-04
+    date: 2023-12-12
     element:
       uris: [ 'material.dart' ]
       variable: 'standardEasing'
@@ -910,9 +910,9 @@ transforms:
           field: legacy
           inClass: Easing
 
-  # Changes made in https://github.com/flutter/flutter/pull/129942
+  # Changes made in https://github.com/flutter/flutter/pull/134417
   - title: "Migrate to 'Easing.legacyAccelerate'"
-    date: 2023-07-04
+    date: 2023-12-12
     element:
       uris: [ 'material.dart' ]
       variable: 'accelerateEasing'
@@ -923,9 +923,9 @@ transforms:
           field: legacyAccelerate
           inClass: Easing
 
-  # Changes made in https://github.com/flutter/flutter/pull/129942
+  # Changes made in https://github.com/flutter/flutter/pull/134417
   - title: "Migrate to 'Easing.legacyDecelerate'"
-    date: 2023-07-04
+    date: 2023-12-12
     element:
       uris: [ 'material.dart' ]
       variable: 'decelerateEasing'

packages/flutter/lib/src/material/curves.dart

@@ -6,33 +6,46 @@ import 'package:flutter/animation.dart';
 
 // The easing curves of the Material Library
 
-// TODO(guidezpl): deprecate the three curves below once customers (packages/plugins) are migrated
-
-/// The standard easing curve in the Material specification.
+/// The standard easing curve in the Material 2 specification.
 ///
 /// Elements that begin and end at rest use standard easing.
 /// They speed up quickly and slow down gradually, in order
 /// to emphasize the end of the transition.
 ///
 /// See also:
 /// * <https://material.io/design/motion/speed.html#easing>
+@Deprecated(
+  'Use Easing.legacy (M2) or Easing.standard (M3) instead. '
+  'This curve is updated in M3. '
+  'This feature was deprecated after v3.18.0-0.1.pre.'
+)
 const Curve standardEasing = Curves.fastOutSlowIn;
 
-/// The accelerate easing curve in the Material specification.
+/// The accelerate easing curve in the Material 2 specification.
 ///
 /// Elements exiting a screen use acceleration easing,
 /// where they start at rest and end at peak velocity.
 ///
 /// See also:
 /// * <https://material.io/design/motion/speed.html#easing>
+@Deprecated(
+  'Use Easing.legacyAccelerate (M2) or Easing.standardAccelerate (M3) instead. '
+  'This curve is updated in M3. '
+  'This feature was deprecated after v3.18.0-0.1.pre.'
+)
 const Curve accelerateEasing = Cubic(0.4, 0.0, 1.0, 1.0);
 
-/// The decelerate easing curve in the Material specification.
+/// The decelerate easing curve in the Material 2 specification.
 ///
 /// Incoming elements are animated using deceleration easing,
 /// which starts a transition at peak velocity (the fastest
 /// point of an element’s movement) and ends at rest.
 ///
 /// See also:
 /// * <https://material.io/design/motion/speed.html#easing>
+@Deprecated(
+  'Use Easing.legacyDecelerate (M2) or Easing.standardDecelerate (M3) instead. '
+  'This curve is updated in M3. '
+  'This feature was deprecated after v3.18.0-0.1.pre.'
+)
 const Curve decelerateEasing = Cubic(0.0, 0.0, 0.2, 1.0);

packages/flutter/test_fixes/material/material.dart

@@ -318,11 +318,10 @@ void main() {
   );
   final Clip clip = details.clipBehavior;
 
-  // Changes made in https://github.com/flutter/flutter/pull/129942
-  // TODO(guidezpl): enable fix after https://github.com/dart-lang/sdk/issues/52902
-  // const Curve curve = standardEasing; expect Easing.legacy
-  // const Curve curve = accelerateEasing; expect Easing.legacyAccelerate
-  // const Curve curve = decelerateEasing; expect Easing.legacyDecelerate
+  // Changes made in https://github.com/flutter/flutter/pull/134417
+  const Curve curve = standardEasing;
+  const Curve curve = accelerateEasing;
+  const Curve curve = decelerateEasing;
 
   final PlatformMenuBar platformMenuBar = PlatformMenuBar(menus: <PlatformMenuItem>[], body: const SizedBox());
   final Widget bodyValue = platformMenuBar.body;

packages/flutter/test_fixes/material/material.dart.expect

@@ -314,11 +314,10 @@ void main() {
   );
   final Clip clip = details.decorationClipBehavior;
 
-  // Changes made in https://github.com/flutter/flutter/pull/129942
-  // TODO(guidezpl): enable fix after https://github.com/dart-lang/sdk/issues/52902
-  // const Curve curve = standardEasing; expect Easing.legacy
-  // const Curve curve = accelerateEasing; expect Easing.legacyAccelerate
-  // const Curve curve = decelerateEasing; expect Easing.legacyDecelerate
+  // Changes made in https://github.com/flutter/flutter/pull/134417
+  const Curve curve = Easing.legacy;
+  const Curve curve = Easing.legacyAccelerate;
+  const Curve curve = Easing.legacyDecelerate;
 
   final PlatformMenuBar platformMenuBar = PlatformMenuBar(menus: <PlatformMenuItem>[], child: const SizedBox());
   final Widget bodyValue = platformMenuBar.child;