[JDK-8252015: [macos11] java.awt.TrayIcon requires updates for template images](https://bugs.openjdk.java.net/browse/JDK-8252015)
### Problem According to Apple's human interface guidelines, developers should use template images for tray icons. This way icons look good when desktop theme or wallpaper change. On the API level, this means setting the `NSImage::isTemplate` flag. Currently there's no way in Java to set this flag. Even if one uses a template (black and transparent pixels only) image, MacOS will treat it as regular image. As a result, the image will not be visible when using dark theme. ### Solution: * If `sun.awt.enableTemplateImages` property is set, all tray icon images are treated as templates. It's the developers' responsibility to ensure their images are indeed templates. This property allows us to avoid new API and accidental behavior changes * Value of this property is passed from Java into `NSImage::setTemplate` * We need the tray icon image rendered by MacOS, so we use a button (rather than a view) to host the image ------------- Commit messages: - 8252015: [macos11] java.awt.TrayIcon requires updates for template images Changes: https://git.openjdk.java.net/jdk/pull/481/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=481&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8252015 Stats: 214 lines in 3 files changed: 69 ins; 81 del; 64 mod Patch: https://git.openjdk.java.net/jdk/pull/481.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/481/head:pull/481 PR: https://git.openjdk.java.net/jdk/pull/481
