Migrate boxInline tests to new multi-file framework

compiler/testData/codegen/boxInline/special/ifBranches.kt

@@ -0,0 +1,73 @@
+// FILE: 1.kt
+
+package test
+
+inline fun <T> runIf(f: (T) -> T, start: T, stop: T, secondStart: T) : T {
+    if (f(start) == stop) {
+        return f(start)
+    }
+    return f(secondStart)
+}
+
+
+inline fun <T> runIf2(f: (T) -> T, start: T, stop: T, secondStart: T) : T {
+    val result = f(start)
+    if (result == stop) {
+        return result
+    }
+    return f(secondStart)
+}
+
+inline fun <T> runIfElse(f: (T) -> T, start: T, stop: T, secondStart: T) : T {
+    if (f(start) == stop) {
+        return f(start)
+    } else {
+        return f(secondStart)
+    }
+}
+
+// FILE: 2.kt
+
+import test.*
+
+fun testIf(): String {
+    if (runIf({it}, 11, 11, 12) != 11) return "testIf 1 test fail"
+    if (runIf({it}, 11, 1, 12) != 12) return "testIf 2 test fail"
+
+    if (runIf({if (it == 11) it else 12}, 11, 11, 0) != 11) return "testIf 3 test fail"
+    if (runIf({if (it == 11) it else 12}, 11, 1, 0) != 12) return "testIf 4 test fail"
+
+    return "OK"
+}
+
+fun testIf2(): String {
+    if (runIf2({it}, 11, 11, 12) != 11) return "testIf2 1 test fail"
+    if (runIf2({it}, 11, 1, 12) != 12) return "testIf2 2 test fail"
+
+    if (runIf2({if (it == 11) it else 12}, 11, 11, 0) != 11) return "testIf2 3 test fail"
+    if (runIf2({if (it == 11) it else 12}, 11, 1, 0) != 12) return "testIf2 4 test fail"
+
+    return "OK"
+}
+
+fun testIfElse(): String {
+    if (runIfElse({it}, 11, 11, 12) != 11) return "testIfElse 1 test fail"
+    if (runIfElse({it}, 11, 1, 12) != 12) return "testIfElse 2 test fail"
+
+    if (runIfElse({if (it == 11) it else 12}, 11, 11, 0) != 11) return "testIfElse 3 test fail"
+    if (runIfElse({if (it == 11) it else 12}, 11, 1, 0) != 12) return "testIfElse 4 test fail"
+    return "OK"
+}
+
+fun box(): String {
+    var result = testIf()
+    if (result != "OK") return "fail1: ${result}"
+
+    result = testIf2()
+    if (result != "OK") return "fail2: ${result}"
+
+    result = testIfElse()
+    if (result != "OK") return "fail2: ${result}"
+
+    return "OK"
+}