Add asm sources into idea sdk sources on the sdk preparation

restores navigation to asm sources in idea.
The asm sources could not be added separately, due to the gradle issue
https://issues.gradle.org/browse/GRADLE-3210

buildSrc/prepare-deps/intellij-sdk/build.gradle.kts

@@ -7,6 +7,16 @@ import org.gradle.api.publish.ivy.internal.publication.DefaultIvyPublicationIden
 import org.gradle.api.publish.ivy.internal.publisher.IvyDescriptorFileGenerator
 import java.io.File
 import org.gradle.internal.os.OperatingSystem
+import com.github.jengelman.gradle.plugins.shadow.tasks.ShadowJar
+
+buildscript {
+    repositories {
+        jcenter()
+    }
+    dependencies {
+        classpath("com.github.jengelman.gradle.plugins:shadow:${property("versions.shadow")}")
+    }
+}
 
 val intellijUltimateEnabled: Boolean by rootProject.extra
 val intellijRepo: String by rootProject.extra
@@ -140,8 +150,10 @@ val unzipIntellijCore by tasks.creating { configureExtractFromConfigurationTask(
 
 val unzipJpsStandalone by tasks.creating { configureExtractFromConfigurationTask(`jps-standalone`) { zipTree(it.singleFile) } }
 
-val copyIntellijSdkSources by tasks.creating {
-    configureExtractFromConfigurationTask(sources) { it.singleFile }
+val copyIntellijSdkSources by tasks.creating(ShadowJar::class.java) {
+    from(sources)
+    from(`asm-shaded-sources`)
+    destinationDir = File(repoDir, sources.name)
 }
 
 val copyJpsBuildTest by tasks.creating { configureExtractFromConfigurationTask(`jps-build-test`) { it.singleFile } }