Do not try building light classes for inline classes in dumb mode

Generation of inline classes is quite complicated: we mangle methods,
 add stubs and synthesized methods. So, for simplicity, to avoid
 logic duplication in dummy resolve and in the backend, currently we
 will use only the latter for light classes generation

 #KT-26843 Fixed

idea/testData/multiFileLocalInspections/unusedSymbol/inlineClassesImplInterface/before/iFace.kt

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

idea/testData/multiFileLocalInspections/unusedSymbol/inlineClassesImplInterface/before/test.kt

@@ -0,0 +1,3 @@
+inline class InlineClass(val x: Int) : IFace {
+    override fun <caret>foo() {}
+}