Create from usage: Do not generate function body if it's declared as a trait member

#KT-6078 Fixed

idea/testData/quickfix/createFromUsage/createFunction/call/afterExtensionFunOnTrait.kt

@@ -0,0 +1,11 @@
+// "Create extension function 'foo'" "true"
+
+trait T
+
+fun test(t: T) {
+    val b: Boolean = t.foo("1", 2)
+}
+
+fun T.foo(s: String, i: Int): Boolean {
+    throw UnsupportedOperationException("not implemented") //To change body of created functions use File | Settings | File Templates.
+}

idea/testData/quickfix/createFromUsage/createFunction/call/afterFunOnTrait.kt

@@ -0,0 +1,9 @@
+// "Create function 'foo'" "true"
+
+trait T {
+    fun foo(s: String, i: Int): Boolean
+}
+
+fun test(t: T) {
+    val b: Boolean = t.foo("1", 2)
+}

idea/testData/quickfix/createFromUsage/createFunction/call/beforeExtensionFunOnTrait.kt

@@ -0,0 +1,7 @@
+// "Create extension function 'foo'" "true"
+
+trait T
+
+fun test(t: T) {
+    val b: Boolean = t.<caret>foo("1", 2)
+}

idea/testData/quickfix/createFromUsage/createFunction/call/beforeFunOnTrait.kt

@@ -0,0 +1,7 @@
+// "Create function 'foo'" "true"
+
+trait T
+
+fun test(t: T) {
+    val b: Boolean = t.<caret>foo("1", 2)
+}