Elements. Remove a few v1 methods from InheritanceManager3.

Replace `getInheritedMap()` with v2 version.
Remove `getMember()`, operations should go thought elements, not types.
Remove `getMember2()`.
Rename v2 `getMember4()` into `getMember()`.

A few internal methods are duplicated for now, will be de-duplicated
when migration of InheritanceManager3 is finished. For now I'd like to
do smaller steps than migrating it fully.

Change-Id: Ib5d9d28e91d77330e41480fcb7176f93d867728a
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/435663
Reviewed-by: Brian Wilkerson <[email protected]>
Reviewed-by: Paul Berry <[email protected]>
Commit-Queue: Konstantin Shcheglov <[email protected]>

Author: scheglov

pkg/analysis_server/lib/src/lsp/handlers/custom/handler_super.dart

@@ -117,7 +117,7 @@ class _SuperComputer {
       return null;
     }
 
-    var member = inheritanceManager.getInherited4(interfaceElement, name);
+    var member = inheritanceManager.getInherited(interfaceElement, name);
     return _lastFragment(member);
   }
 

pkg/analyzer/lib/src/dart/element/element.dart

@@ -5323,14 +5323,14 @@ abstract class InterfaceElementImpl extends InstanceElementImpl
 
   @override
   ExecutableElement? getInheritedMember(Name name) =>
-      (session as AnalysisSessionImpl).inheritanceManager.getInherited4(
+      (session as AnalysisSessionImpl).inheritanceManager.getInherited(
         this,
         name,
       );
 
   @override
   ExecutableElement? getInterfaceMember(Name name) =>
-      (session as AnalysisSessionImpl).inheritanceManager.getMember4(
+      (session as AnalysisSessionImpl).inheritanceManager.getMember(
         this,
         name,
       );
@@ -5472,7 +5472,7 @@ abstract class InterfaceElementImpl extends InstanceElementImpl
     required LibraryElement library,
   }) {
     return inheritanceManager
-        .getInherited4(this, Name.forLibrary(library, methodName))
+        .getInherited(this, Name.forLibrary(library, methodName))
         .ifTypeOrNull();
   }