Don't show type hint for local variable initialized with object

#KT-17964 Fixed

idea/src/org/jetbrains/kotlin/idea/parameterInfo/TypeHints.kt

@@ -54,6 +54,11 @@ fun provideTypeHint(element: KtCallableDeclaration, offset: Int): List<InlayInfo
     if (type.containsError()) return emptyList()
     val name = type.constructor.declarationDescriptor?.name
     if (name == SpecialNames.NO_NAME_PROVIDED) {
+        if (element is KtProperty && element.isLocal) {
+            // for local variables, an anonymous object type is not collapsed to its supertype,
+            // so showing the supertype will be misleading
+            return emptyList()
+        }
         type = type.immediateSupertypes().singleOrNull() ?: return emptyList()
     }
     else if (name?.isSpecial == true) {

idea/tests/org/jetbrains/kotlin/idea/parameterInfo/InlayTypeHintsTest.kt

@@ -96,4 +96,13 @@ class InlayTypeHintsTest : KotlinLightCodeInsightFixtureTestCase() {
                   }
               }""")
     }
+
+    fun testAnonymousObjectNoBaseType() {
+        HintType.LOCAL_VARIABLE_HINT.option.set(true)
+        check("""fun foo() {
+                val o = object {
+                    val x: Int = 0
+                }
+              }""")
+    }
 }