core: fix links for fields in nested classes

jadx-core/src/main/java/jadx/api/JavaClass.java

@@ -116,7 +116,9 @@ public final class JavaClass implements JavaNode {
 	public CodePosition getDefinitionPosition(int line, int offset) {
 		Map<CodePosition, Object> map = getCodeAnnotations();
 		Object obj = map.get(new CodePosition(line, offset));
-		if (obj instanceof LineAttrNode) {
+		if (!(obj instanceof LineAttrNode)) {
+			return null;
+		}
 		ClassNode clsNode = null;
 		if (obj instanceof ClassNode) {
 			clsNode = (ClassNode) obj;
@@ -128,17 +130,18 @@ public final class JavaClass implements JavaNode {
 		if (clsNode == null) {
 			return null;
 		}
-			clsNode = clsNode.getParentClass();
+		clsNode = clsNode.getTopParentClass();
 		JavaClass jCls = decompiler.findJavaClass(clsNode);
 		if (jCls == null) {
 			return null;
 		}
 		jCls.decompile();
 		int defLine = ((LineAttrNode) obj).getDecompiledLine();
-			return new CodePosition(jCls, defLine, 0);
-		}
+		if (defLine == 0) {
 			return null;
 		}
+		return new CodePosition(jCls, defLine, 0);
+	}
 
 	public Integer getSourceLine(int decompiledLine) {
 		decompile();

jadx-core/src/main/java/jadx/core/dex/nodes/ClassNode.java

@@ -354,6 +354,11 @@ public class ClassNode extends LineAttrNode implements ILoadable {
 		return parentClass;
 	}
 
+	public ClassNode getTopParentClass() {
+		ClassNode parent = getParentClass();
+		return parent == this ? this : parent.getParentClass();
+	}
+
 	public List<ClassNode> getInnerClasses() {
 		return innerClasses;
 	}