IDEA-CR-36156 restore license for Eclipse

platform/build-scripts/groovy/org/jetbrains/intellij/build/CommunityLibraryLicenses.groovy

@@ -145,6 +145,9 @@ class CommunityLibraryLicenses {
                        url: "http://docutils.sourceforge.net/"),
     new LibraryLicense(name: "DTDParser", version: "1.13", license: "LGPL", url: "http://sourceforge.net/projects/dtdparser/",
                        licenseUrl: "http://www.opensource.org/licenses/lgpl-2.1"),
+    // see BaseIdeaProperties.groovy
+    new LibraryLicense(name: "Eclipse JDT Core", libraryName: "Eclipse", attachedTo: "intellij.platform.ide", version: "4.2.1", license: "CPL 1.0",
+                       url: "http://www.eclipse.org/jdt/core/index.php"),
     new LibraryLicense(name: "EdDSA-Java", libraryName: "eddsa", version: "0.2.0", license: "CC0 1.0 Universal",
                        licenseUrl: "https://github.com/str4d/ed25519-java/blob/master/LICENSE.txt",
                        url: "https://github.com/str4d/ed25519-java"),

platform/build-scripts/testFramework/src/org/jetbrains/intellij/build/LibraryLicensesTester.kt

@@ -23,7 +23,11 @@ class LibraryLicensesTester(private val project: JpsProject, private val license
     }
 
     val librariesWithLicenses = licenses.flatMapTo(THashSet()) { it.libraryNames }
-    val unusedLibrariesWithLicenses = licenses.filter { it.libraryName != null }.mapNotNullTo(THashSet()) { it.libraryName }
+    val unusedLibrariesWithLicenses = licenses
+      .mapNotNullTo(THashSet()) {
+        // for some libs (e.g. Eclipse both libraryName and attachedTo specified because of tricky layout)
+        if (it.libraryName != null && it.attachedTo == null) it.libraryName else null
+      }
 
     // what for?
     unusedLibrariesWithLicenses.remove("Servlets")