Do not report experimental usage errors in import statements

#KT-25545 Fixed

compiler/testData/diagnostics/testsWithStdLib/experimental/importStatement.kt

@@ -0,0 +1,27 @@
+// !USE_EXPERIMENTAL: kotlin.Experimental
+// FILE: api.kt
+
+package feature.experimental.self
+
+@Experimental
+annotation class ImportedMarker
+
+@ImportedMarker
+object ImportedClass {
+    @ImportedMarker
+    fun importedObjectMember() {}
+}
+
+@ImportedMarker
+fun importedFunction() {}
+
+@ImportedMarker
+val importedProperty = Unit
+
+// FILE: usage.kt
+
+import feature.experimental.self.ImportedMarker
+import feature.experimental.self.ImportedClass
+import feature.experimental.self.importedFunction
+import feature.experimental.self.importedProperty
+import feature.experimental.self.ImportedClass.importedObjectMember

compiler/testData/diagnostics/testsWithStdLib/experimental/importStatement.txt

@@ -0,0 +1,27 @@
+package
+
+package feature {
+
+    package feature.experimental {
+
+        package feature.experimental.self {
+            @feature.experimental.self.ImportedMarker public val importedProperty: kotlin.Unit
+            @feature.experimental.self.ImportedMarker public fun importedFunction(): kotlin.Unit
+
+            @feature.experimental.self.ImportedMarker public object ImportedClass {
+                private constructor ImportedClass()
+                public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+                public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+                @feature.experimental.self.ImportedMarker public final fun importedObjectMember(): kotlin.Unit
+                public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+            }
+
+            @kotlin.Experimental public final annotation class ImportedMarker : kotlin.Annotation {
+                public constructor ImportedMarker()
+                public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+                public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+                public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+            }
+        }
+    }
+}