Support nested classes in KotlinCliJavaFileManagerImpl.findClass

findClass(String, GlobalSearchScope) is invoked for example when we're
resolving supertypes of classes in Java libraries. Previously, it never
found nested classes and falled back to CoreJavaFileManager's
implementation, which lacks a fix for the original issue (KT-12664,
which was fixed in JvmDependenciesIndex in 5a533a52 and 164c72e8)

 #KT-16931 Fixed

jps-plugin/testData/general/SourcePackagePrefixWithInnerClasses/src/JavaWithInner.java

@@ -0,0 +1,14 @@
+package xxx;
+
+import xxx.JavaWithInner.TableRenderer.TableRow;
+
+public class JavaWithInner {
+    public static class TableRenderer{
+        public interface TableRow {
+        }
+    }
+
+    public static class TextRenderer implements TableRow {
+        public void method() {}
+    }
+}

jps-plugin/testData/general/SourcePackagePrefixWithInnerClasses/src/test.kt

@@ -0,0 +1,3 @@
+package xxx
+
+val test = JavaWithInner.TextRenderer().method()