Change FUNCTION_EXPRESSION_WITH_NAME severity to ERROR

Also drop deprecation related parts and get rid of usages of this `feature` within testData

idea/testData/debugger/tinyApp/src/evaluate/singleBreakpoint/lambdas/oneLineFunctionalExpression.kt

@@ -6,7 +6,7 @@ fun main(args: Array<String>) {
     // RESULT: 1: I
     // STEP_INTO: 2
     //Breakpoint!
-    a.foo (fun b(it): A { return a })
+    a.foo (fun(it): A { return a })
 }
 
 class A {

idea/testData/inspections/cleanup/cleanup.kt

@@ -4,8 +4,6 @@ import pack.oldFun3
 
 class A private()
 
-val x = fun foo(x: String) { }
-
 fun foo() {
     @loop
     for (i in 1..100) {

idea/testData/inspections/cleanup/cleanup.kt.after

@@ -3,8 +3,6 @@ import pack.oldFun2 // should not be removed for non-deprecated overload used
 
 class A private constructor()
 
-val x = fun(x: String) { }
-
 fun foo() {
     loop@
     for (i in 1..100) {

idea/testData/quickfix/migration/removeNameFromFunctionExpression/manyFilesMuitliple.after.data.Sample.kt

@@ -1,3 +0,0 @@
-fun main() {
-    (fun() {})
-}

idea/testData/quickfix/migration/removeNameFromFunctionExpression/manyFilesMuitliple.after.kt

@@ -1,46 +0,0 @@
-// "Remove identifier from function expressions in the whole project" "true"
-
-inline fun run(block: () -> Unit) = block()
-annotation class ann
-
-fun foo() {
-    l2@ @ann l2@ fun local() {
-        run(l1@ fun() { return@l1 })
-
-        run(label@ expr@ fun() {
-            return@label
-            return@expr
-        })
-    }
-}
-
-class A {
-    fun bar() {
-        run(toRun@ fun() {
-            if (1 == 1) return@toRun
-            return@bar
-        })
-
-        run(
-                /* abc */  fun /* cde */ () {
-                    return@bar
-                }
-        )
-
-        run(
-                /* abc */
-                foo@ fun /* cde */ () {
-                    return@foo
-                }
-        )
-    }
-
-    init {
-        (foo@ fun A.() {
-            (fun() {
-                val x = 1
-            })
-            return@foo
-        })
-    }
-}

idea/testData/quickfix/migration/removeNameFromFunctionExpression/manyFilesMuitliple.before.Main.kt

@@ -1,46 +0,0 @@
-// "Remove identifier from function expressions in the whole project" "true"
-
-inline fun run(block: () -> Unit) = block()
-annotation class ann
-
-fun foo() {
-    l2@ @ann l2@ fun local() {
-        run(l1@ fun() { return@l1 })
-
-        run(label@ fun expr<caret>() {
-            return@label
-            return@expr
-        })
-    }
-}
-
-class A {
-    fun bar() {
-        run(fun toRun() {
-            if (1 == 1) return@toRun
-            return@bar
-        })
-
-        run(
-                /* abc */  fun /* cde */ toRun() {
-                    return@bar
-                }
-        )
-
-        run(
-                /* abc */
-                fun /* cde */ foo() {
-                    return@foo
-                }
-        )
-    }
-
-    init {
-        (fun A.foo() {
-            (fun bar() {
-                val x = 1
-            })
-            return@foo
-        })
-    }
-}

idea/testData/quickfix/migration/removeNameFromFunctionExpression/manyFilesMuitliple.before.data.Sample.kt

@@ -1,3 +0,0 @@
-fun main() {
-    (fun foo() {})
-}