[build][native] don't ever fix dist, take it with API

kotlin-native/build-tools/src/main/groovy/org/jetbrains/kotlin/KonanTest.groovy

@@ -21,6 +21,7 @@ import org.gradle.api.tasks.JavaExec
 import org.gradle.api.tasks.TaskAction
 import org.gradle.process.ExecResult
 import org.jetbrains.kotlin.utils.DFS
+import org.jetbrains.kotlin.*
 
 import java.nio.file.Paths
 import java.util.function.Function
@@ -83,6 +84,7 @@ class RunExternalTestGroup extends JavaExec implements CompilerRunner {
                 include '*.jar'
             }
             jvmArgs "-Xmx4G"
+            jvmArgs "-Dkonan.home=${UtilsKt.getKotlinNativeDist(project)}"
             enableAssertions = true
             def sources = File.createTempFile(name,".lst")
             sources.deleteOnExit()

kotlin-native/build-tools/src/main/kotlin/org/jetbrains/kotlin/CacheTesting.kt

@@ -35,15 +35,7 @@ fun configureCacheTesting(project: Project): CacheTesting? {
             cacheDir.mkdirs()
         }
 
-        if (!(project.property("useCustomDist") as Boolean)) {
-            val tasks = listOf(
-                    "${target}CrossDist",
-                    "${target}CrossDistRuntime",
-                    "distCompiler"
-            ).map { task -> project.rootProject.tasks.getByName(task) }
-
-            dependsOn(tasks)
-        }
+        dependsOnDist()
 
         commandLine(
                 "$dist/bin/konanc",

kotlin-native/build-tools/src/main/kotlin/org/jetbrains/kotlin/Utils.kt

@@ -50,10 +50,15 @@ val Project.testOutputFramework
 val Project.testOutputExternal
     get() = (findProperty("testOutputExternal") as File).toString()
 
+val validPropertiesNames = listOf("kotlin.native.home",
+                                  "org.jetbrains.kotlin.native.home",
+                                  "konan.home")
+
 val Project.kotlinNativeDist
-    get() = this.rootProject.file(findProperty("kotlin.native.home")
-                                      ?: findProperty("org.jetbrains.kotlin.native.home")
-                                      ?: findProperty("konan.home") ?: "dist")
+    get() = rootProject.file(validPropertiesNames.firstOrNull{ hasProperty(it) }?.let{ findProperty(it) } ?: "dist")
+
+val kotlinNativeHome
+    get() = validPropertiesNames.mapNotNull(System::getProperty).first()
 
 val Project.useCustomDist
     get() = hasProperty("kotlin.native.home") ||
@@ -132,15 +137,12 @@ fun Project.dependsOnDist(taskName: String) {
 }
 
 fun Task.dependsOnDist() {
-    // We don't build the compiler if a custom dist path is specified.
-    if (!(project.findProperty("useCustomDist") as Boolean)) {
-        dependsOn(":kotlin-native:dist")
-        val target = project.testTarget
-        if (target != HostManager.host) {
-            // if a test_target property is set then tests should depend on a crossDist
-            // otherwise, runtime components would not be build for a target.
-            dependsOn(":kotlin-native:${target.name}CrossDist")
-        }
+    dependsOn(":kotlin-native:dist")
+    val target = project.testTarget
+    if (target != HostManager.host) {
+        // if a test_target property is set then tests should depend on a crossDist
+        // otherwise, runtime components would not be build for a target.
+        dependsOn(":kotlin-native:${target.name}CrossDist")
     }
 }