KSCM: persist script dependencies between idea launches

idea/idea-core/src/org/jetbrains/kotlin/idea/core/script/KotlinScriptConfigurationManager.kt

@@ -155,13 +155,26 @@ class KotlinScriptConfigurationManager(
 
     fun <TF : Any> getExternalImports(file: TF): KotlinScriptExternalDependencies = cacheLock.read {
         val path = getFilePath(file)
-        cache[path]?.dependencies?.let { return it }
+        val cached = cache[path]
+        cached?.dependencies?.let { return it }
+
+        tryLoadingFromDisk(cached, file, path)
 
         updateExternalImportsCache(listOf(file))
 
         return cache[path]?.dependencies ?: NoDependencies
     }
 
+    private fun <TF : Any> tryLoadingFromDisk(cached: DataAndRequest?, file: TF, path: String) {
+        if (cached != null || file !is VirtualFile) return
+
+        ScriptDependenciesFileAttribute.read(file)?.let { deserialized ->
+            save(path, deserialized, file, persist = false)
+            invalidateLocalCaches()
+            notifyRootsChanged()
+        }
+    }
+
     private fun <TF: Any> updateExternalImportsCache(files: Iterable<TF>) = cacheLock.write {
         files.mapNotNull { file ->
             scriptDefinitionProvider.findScriptDefinition(file)?.let {