Decorations: Remove DecorationsProvider#adjustWindowInsets

It was only used on Windows, where it is currently always
an effective no-op as the insets were adjusted by zero
values. In fact with non-zero adjustments the result was
an incorrectly sized window.

core/src/main/java/com/github/weisj/darklaf/platform/DecorationsHandler.java

@@ -110,8 +110,4 @@ public class DecorationsHandler {
     public void adjustContentArea(final JRootPane root, final Rectangle rect) {
         decorationsProvider.adjustContentArea(root, rect);
     }
-
-    public void adjustWindowInsets(final Window window, final Insets i) {
-        decorationsProvider.adjustWindowInsets(window, i);
-    }
 }

platform-base/src/main/java/com/github/weisj/darklaf/platform/decorations/DecorationsProvider.java

@@ -70,12 +70,4 @@ public interface DecorationsProvider {
      * @param rect the proposed content area.
      */
     default void adjustContentArea(final JRootPane root, final Rectangle rect) {}
-
-    /**
-     * Adjust the window insets.
-     *
-     * @param window the corresponding window.
-     * @param i the insets to adjust.
-     */
-    default void adjustWindowInsets(final Window window, final Insets i) {}
 }

windows/src/main/java/com/github/weisj/darklaf/platform/windows/WindowsDecorationsProvider.java

@@ -98,18 +98,6 @@ public class WindowsDecorationsProvider implements DecorationsProvider {
         }
     }
 
-    @Override
-    public void adjustWindowInsets(final Window window, final Insets i) {
-        // Compensate for the insets of the native window peer that include the decorations.
-        if (window != null) {
-            Insets insets = window.getInsets();
-            i.left -= insets.left;
-            i.right -= insets.right;
-            i.top -= insets.top;
-            i.bottom -= insets.bottom;
-        }
-    }
-
     @Override
     public void loadDecorationProperties(final Properties properties, final UIDefaults currentDefaults) {
         IconLoader iconLoader = IconLoader.get(WindowsDecorationsProvider.class);