'when' should use intrinsics for '=='

#KT-19029 Fixed Target versions 1.1.5
 #KT-18818 Fixed Target versions 1.1.5

compiler/testData/codegen/bytecodeText/when/kt18818.kt

@@ -0,0 +1,14 @@
+// WITH_RUNTIME
+
+fun findUserId(username: String): Long? = null
+
+fun main(args: Array<String>) {
+    val userId = findUserId("abcd")
+
+    when (userId) {
+        null -> println("User not found")
+        else -> println("User ID: $userId")
+    }
+}
+
+// 0 areEqual

compiler/testData/codegen/bytecodeText/when/noBoxingInDefaultWhenWithSpecialCases.kt

@@ -0,0 +1,27 @@
+// FILE: C.kt
+class CInt(val value: Int)
+val nCInt3: CInt? = CInt(3)
+
+class CLong(val value: Long)
+val nCLong3: CLong? = CLong(3)
+
+// FILE: test.kt
+fun testInt(i: Int?) =
+        when (i) {
+            0 -> "zero"
+            42 -> "magic"
+            else -> "other"
+        }
+
+fun testLong(i: Long?) =
+        when (i) {
+            0L -> "zero"
+            42L -> "magic"
+            else -> "other"
+        }
+
+// @TestKt.class:
+// 0 valueOf
+// 0 Integer.valueOf
+// 0 Long.valueOf
+// 0 areEqual

compiler/testData/codegen/bytecodeText/when/whenNull.kt

@@ -0,0 +1,10 @@
+fun test(a: Any?, b: Any?, c: Any?) {
+    when (null) {
+        a -> throw IllegalArgumentException("a is null")
+        b -> throw IllegalArgumentException("b is null")
+        c -> throw IllegalArgumentException("c is null")
+    }
+}
+
+// 0 areEqual
+// 3 IFNONNULL

compiler/testData/codegen/bytecodeText/when/whenZero.kt

@@ -0,0 +1,10 @@
+fun test(a: Int, b: Int, c: Int) {
+    when (0) {
+        a -> throw IllegalArgumentException("a is 0")
+        b -> throw IllegalArgumentException("b is 0")
+        c -> throw IllegalArgumentException("c is 0")
+    }
+}
+
+// 0 IF_ICMPNE
+// 3 IFNE