[Metadata] Emit ModuleFragment for each part of package name

Some libraries (e.g. `klib contents`) expects this kind of behaviour.

Interop/StubGenerator/src/main/kotlin/org/jetbrains/kotlin/native/interop/gen/StubIrMetadataEmitter.kt

@@ -21,7 +21,21 @@ class StubIrMetadataEmitter(
     }
 
     private fun emitModuleFragments(): List<KmModuleFragment> =
-            ModuleMetadataEmitter(context.configuration.pkgName, builderResult.stubs).emit().let(::listOf)
+            ModuleMetadataEmitter(
+                    context.configuration.pkgName,
+                    builderResult.stubs
+            ).emit().let { kmModuleFragment ->
+                // We need to create module fragment for each part of package name.
+                val pkgName = context.configuration.pkgName
+                val fakePackages = pkgName.mapIndexedNotNull { idx, char ->
+                    if (char == '.') idx else null
+                }.map { dotPosition ->
+                    KmModuleFragment().also {
+                        it.fqName = pkgName.substring(0, dotPosition)
+                    }
+                }
+                fakePackages + kmModuleFragment
+            }
 }
 
 /**

Interop/StubGenerator/src/main/kotlin/org/jetbrains/kotlin/native/interop/gen/jvm/InteropLibraryCreation.kt

@@ -88,6 +88,14 @@ class ChunkingWriteStrategy(
                         }
                     }
                 }
-        return classFragments + packageFragments
+        val result = classFragments + packageFragments
+        return if (result.isEmpty()) {
+            // We still need to emit empty packages because they may
+            // represent parts of package declaration (e.g. platform.[]).
+            // Tooling (e.g. `klib contents`) expects this kind of behavior.
+            parts
+        } else {
+            result
+        }
     }
 }