Put argument name hint before spread element

#KT-21645 Fixed

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

@@ -69,7 +69,8 @@ private fun getParameterInfoForCallCandidate(resolvedCall: ResolvedCall<out Call
             arg.getArgumentExpression()?.let { argExp ->
                 if (!arg.isNamed() && !valueParam.name.isSpecial && argExp.isUnclearExpression()) {
                     val prefix = if (valueParam.varargElementType != null) "..." else ""
-                    return@mapNotNull InlayInfo(prefix + valueParam.name.identifier, argExp.startOffset)
+                    return@mapNotNull InlayInfo(prefix + valueParam.name.identifier,
+                                                arg.getSpreadElement()?.startOffset ?: argExp.startOffset)
                 }
             }
         }

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

@@ -178,4 +178,10 @@ annotation class ManyArgs(val name: String, val surname: String)
             x.foo("123")
         }""")
     }
+
+    fun `test spread`() {
+        check("""fun foo(vararg x: Int) {
+            intArrayOf(1, 0).apply { foo(<hint text="...x:" />*this) }
+        }""")
+    }
 }