Java IC compatibility fix for Gradle 2.14+

Added version check to switch between old and new approaches because
Gradle versions before 2.14 have a bug in Java IC.
Added Kotlin classes to Java task input.
Added  annotationsFile into task input to include it into up-to-date check.

Related issues: #KT-16585 Fixed

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/plugin/KotlinPlugin.kt

@@ -31,6 +31,7 @@ import org.jetbrains.kotlin.gradle.internal.Kapt3KotlinGradleSubplugin.Companion
 import org.jetbrains.kotlin.gradle.internal.initKapt
 import org.jetbrains.kotlin.gradle.plugin.android.AndroidGradleWrapper
 import org.jetbrains.kotlin.gradle.tasks.*
+import org.jetbrains.kotlin.gradle.utils.ParsedGradleVersion
 import org.jetbrains.kotlin.incremental.configureMultiProjectIncrementalCompilation
 import org.jetbrains.kotlin.incremental.multiproject.ArtifactDifferenceRegistryProviderAndroidWrapper
 import java.io.File
@@ -520,19 +521,25 @@ internal open class KotlinAndroidPlugin(
 }
 
 private fun configureJavaTask(kotlinTask: KotlinCompile, javaTask: AbstractCompile, logger: Logger) {
-    // Since we cannot update classpath statically, java not able to detect changes in the classpath after kotlin compiler.
-    // Therefore this (probably inefficient since java cannot decide "uptodateness" by the list of changed class files, but told
-    // explicitly being out of date whenever any kotlin files are compiled
+    // Gradle Java IC in older Gradle versions (before 2.14) cannot check .class directories updates.
+    // To make it work, reset the up-to-date status of compileJava with this flag.
     kotlinTask.anyClassesCompiled = false
-
-    javaTask.outputs.upToDateWhen { task ->
-        val kotlinClassesCompiled = kotlinTask.anyClassesCompiled
-        if (kotlinClassesCompiled) {
-            logger.info("Marking $task out of date, because kotlin classes are changed")
+    val gradleSupportsJavaIcWithClassesDirs = ParsedGradleVersion.parse(javaTask.project.gradle.gradleVersion)
+                                                      ?.let { it >= ParsedGradleVersion(2, 14) } ?: false
+    if (!gradleSupportsJavaIcWithClassesDirs) {
+        javaTask.outputs.upToDateWhen { task ->
+            if (kotlinTask.anyClassesCompiled) {
+                logger.info("Marking $task out of date, because kotlin classes are changed")
+                false
+            } else true
         }
-        !kotlinClassesCompiled
     }
 
+    // Make Gradle check if the javaTask is up-to-date based on the Kotlin classes
+    javaTask.inputs.dir(kotlinTask.destinationDir)
+    // Also, use kapt1 annotations file for up-to-date check since annotation processing is done with javac
+    kotlinTask.kaptOptions.annotationsFile?.let { javaTask.inputs.file(it) }
+
     javaTask.dependsOn(kotlinTask.name)
     /*
      * It's important to modify javaTask.classpath only in doFirst,