KT-49089 Fix using @OptionalExpectation annotations from dependencies

Fix the behavior of the common (metadata KLIB) compiler with
hierarchical project structures support as
it analyses usages of annotations from dependencies that are marked
with `@OptionalExpectations`.

The fix on the Kotlin Gradle plugin side is to add the
-Xcommon-sources=... compiler argument to those the invocations of the
compiler, just as it is done with the other compilers.

Issue #KT-49089 Verification Pending

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/kotlin/org/jetbrains/kotlin/gradle/NewMultiplatformIT.kt

@@ -34,6 +34,7 @@ import java.util.jar.JarFile
 import java.util.zip.ZipFile
 import kotlin.test.assertEquals
 import kotlin.test.assertFalse
+import kotlin.test.assertNotNull
 import kotlin.test.assertTrue
 
 class NewMultiplatformIT : BaseGradleIT() {
@@ -1161,6 +1162,17 @@ class NewMultiplatformIT : BaseGradleIT() {
             """.trimIndent()
         )
 
+        build("compileCommonMainKotlinMetadata") {
+            assertSuccessful()
+            val compilerArgsLine = output.lines().singleOrNull { ":compileCommonMainKotlinMetadata Kotlin compiler args" in it }
+            assertNotNull(compilerArgsLine, "The debug log should contain the compiler args for the task :compileCommonMainKotlinMetadata")
+            val args = compilerArgsLine.split(" ")
+            val xCommonSourcesArg = args.singleOrNull { it.startsWith("-Xcommon-sources=") }
+            assertNotNull(xCommonSourcesArg, "The compiler args for K2Metadata should contain the -Xcommon-sources argument")
+            val xCommonSourcesFiles = xCommonSourcesArg.substringAfter("-Xcommon-sources=").split(",")
+            assertTrue { xCommonSourcesFiles.any { it.endsWith("Optional.kt") } }
+        }
+
         build("compileKotlinJvmWithoutJava", "compileKotlinLinux64") {
             assertSuccessful()
             assertFileExists(targetClassesDir("jvmWithoutJava") + "OptionalCommonUsage.class")

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

@@ -116,10 +116,12 @@ internal open class GradleCompilerRunner(
      */
     fun runMetadataCompilerAsync(
         kotlinSources: List<File>,
+        kotlinCommonSources: List<File>,
         args: K2MetadataCompilerArguments,
         environment: GradleCompilerEnvironment
     ): WorkQueue? {
         args.freeArgs += kotlinSources.map { it.absolutePath }
+        args.commonSources = kotlinCommonSources.map { it.absolutePath }.toTypedArray()
         return runCompilerAsync(KotlinCompilerClass.METADATA, args, environment)
     }
 

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

@@ -150,6 +150,11 @@ abstract class KotlinCompileCommon @Inject constructor(
             reportingSettings = reportingSettings(),
             outputFiles = allOutputFiles()
         )
-        compilerRunner.runMetadataCompilerAsync(sourceRoots.kotlinSourceFiles.files.toList(), args, environment)
+        compilerRunner.runMetadataCompilerAsync(
+            sourceRoots.kotlinSourceFiles.files.toList(),
+            commonSourceSet.files.toList(),
+            args,
+            environment
+        )
     }
 }