Apply rainbow highlighting in anonymous initializers

#KT-18839 Fixed

idea/src/org/jetbrains/kotlin/idea/highlighter/KotlinRainbowVisitor.kt

@@ -91,7 +91,9 @@ class KotlinRainbowVisitor : RainbowVisitor() {
             return
         }
 
-        val context = target.getStrictParentOfType<KtDeclarationWithBody>() ?: return
+        val context = target.getStrictParentOfType<KtDeclarationWithBody>()
+                ?: target.getStrictParentOfType<KtAnonymousInitializer>()
+                ?: return
         addInfo(getInfo(context, rainbowElement, rainbowElement.text, attributesKeyToUse))
     }
 

idea/tests/org/jetbrains/kotlin/idea/highlighter/KotlinRainbowHighlighterTest.kt

@@ -83,6 +83,24 @@ class KotlinRainbowHighlighterTest : KotlinLightCodeInsightFixtureTestCase() {
         """)
     }
 
+    fun testInitBlock() {
+        checkRainbow("""
+            class Some {
+                init {
+                    val <rainbow color='ff000004'>x</rainbow> = 128
+                    println(<rainbow color='ff000004'>x</rainbow>)
+
+                    run {
+                        println(<rainbow color='ff000004'>x</rainbow>)
+                    }
+                    fun some() {
+                        val <rainbow color='ff000003'>b</rainbow> = 299
+                        println(<rainbow color='ff000003'>b</rainbow> + <rainbow color='ff000004'>x</rainbow>)
+                    }
+                }
+            }""")
+    }
+
     private fun checkRainbow(code: String) {
         myFixture.testRainbow("rainbow.kt", code, true, true)
     }