Introduce -Xcommon-sources and pass it correctly from build tool plugins

#KT-25196 In Progress

compiler/cli/cli-common/src/org/jetbrains/kotlin/cli/common/arguments/CommonCompilerArguments.kt

@@ -180,6 +180,14 @@ abstract class CommonCompilerArguments : CommonToolArguments() {
     )
     var metadataVersion: String? by FreezableVar(null)
 
+    @Argument(
+        value = "-Xcommon-sources",
+        valueDescription = "<path>",
+        description = "Sources of the common module that need to be compiled together with this module in the multi-platform mode.\n" +
+                "Should be a subset of sources passed as free arguments"
+    )
+    var commonSources: Array<String>? by FreezableVar(null)
+
     open fun configureAnalysisFlags(collector: MessageCollector): MutableMap<AnalysisFlag<*>, Any> {
         return HashMap<AnalysisFlag<*>, Any>().apply {
             put(AnalysisFlag.skipMetadataVersionCheck, skipMetadataVersionCheck)

compiler/cli/cli-common/src/org/jetbrains/kotlin/cli/common/modules/ModuleBuilder.kt

@@ -21,11 +21,12 @@ import org.jetbrains.kotlin.modules.Module
 import java.util.*
 
 class ModuleBuilder(
-        private val name: String,
-        private val outputDir: String,
-        private val type: String
+    private val name: String,
+    private val outputDir: String,
+    private val type: String
 ) : Module {
     private val sourceFiles = ArrayList<String>()
+    private val commonSourceFiles = ArrayList<String>()
     private val classpathRoots = ArrayList<String>()
     private val javaSourceRoots = ArrayList<JavaRootPath>()
     private val friendDirs = ArrayList<String>()
@@ -35,6 +36,10 @@ class ModuleBuilder(
         sourceFiles.add(path)
     }
 
+    fun addCommonSourceFiles(path: String) {
+        commonSourceFiles.add(path)
+    }
+
     fun addClasspathEntry(path: String) {
         classpathRoots.add(path)
     }
@@ -51,6 +56,7 @@ class ModuleBuilder(
     override fun getFriendPaths(): List<String> = friendDirs
     override fun getJavaSourceRoots(): List<JavaRootPath> = javaSourceRoots
     override fun getSourceFiles(): List<String> = sourceFiles
+    override fun getCommonSourceFiles(): List<String> = commonSourceFiles
     override fun getClasspathRoots(): List<String> = classpathRoots
     override fun getModuleName(): String = name
     override fun getModuleType(): String = type

compiler/cli/cli-common/src/org/jetbrains/kotlin/cli/common/modules/ModuleXmlParser.java

@@ -47,6 +47,7 @@ public class ModuleXmlParser {
     public static final String OUTPUT_DIR = "outputDir";
     public static final String FRIEND_DIR = "friendDir";
     public static final String SOURCES = "sources";
+    public static final String COMMON_SOURCES = "commonSources";
     public static final String JAVA_SOURCE_ROOTS = "javaSourceRoots";
     public static final String JAVA_SOURCE_PACKAGE_PREFIX = "packagePrefix";
     public static final String PATH = "path";
@@ -159,6 +160,10 @@ public class ModuleXmlParser {
                 String path = getAttribute(attributes, PATH, qName);
                 moduleBuilder.addSourceFiles(path);
             }
+            else if (COMMON_SOURCES.equalsIgnoreCase(qName)) {
+                String path = getAttribute(attributes, PATH, qName);
+                moduleBuilder.addCommonSourceFiles(path);
+            }
             else if (FRIEND_DIR.equalsIgnoreCase(qName)) {
                 String path = getAttribute(attributes, PATH, qName);
                 moduleBuilder.addFriendDir(path);