Gradle: compile tests incrementally when main is changed

#KT-17674 fixed

compiler/daemon/daemon-common/src/org/jetbrains/kotlin/daemon/common/CompilationOptions.kt

@@ -48,7 +48,9 @@ class IncrementalCompilationOptions(
         /** @See [ReportSeverity] */
         reportSeverity: Int,
         /** @See [CompilationResultCategory]] */
-        requestedCompilationResults: Array<Int>
+        requestedCompilationResults: Array<Int>,
+        val resultDifferenceFile: File? = null,
+        val friendDifferenceFile: File? = null
 ) : CompilationOptions(compilerMode, targetPlatform, reportCategories, reportSeverity, requestedCompilationResults) {
     companion object {
         const val serialVersionUID: Long = 0

compiler/daemon/src/org/jetbrains/kotlin/daemon/CompileServiceImpl.kt

@@ -507,9 +507,12 @@ class CompileServiceImpl(
                                           workingDir,
                                           enabled = true)
 
-        return IncrementalJvmCompilerRunner(workingDir, javaSourceRoots, versions, reporter, annotationFileUpdater,
-                                            artifactChanges, changesRegistry)
-                .compile(allKotlinFiles, k2jvmArgs, compilerMessageCollector, { changedFiles })
+        val compiler = IncrementalJvmCompilerRunner(workingDir, javaSourceRoots, versions,
+                                                    reporter, annotationFileUpdater,
+                                                    artifactChanges, changesRegistry,
+                                                    buildHistoryFile = incrementalCompilationOptions.resultDifferenceFile,
+                                                    friendBuildHistoryFile = incrementalCompilationOptions.friendDifferenceFile)
+        return compiler.compile(allKotlinFiles, k2jvmArgs, compilerMessageCollector, { changedFiles })
     }
 
     override fun leaseReplSession(