Refactor: Move Cocoa-specific DPI methods to CocoaDPIUtil

[ShahzaibIbrahim]

The autoScale methods no longer have relevance in the Win32 implementation, so this commit extracts the macOS-specific DPI scaling logic into a dedicated CocoaDPIUtil class. This improves platform separation and maintains cleaner, OS-specific code boundaries.

[github-actions]

Test Results

   539 files   -  6     539 suites   - 6   31m 49s ⏱️ + 1m 49s
 4 368 tests  - 37   4 352 ✅  - 35   15 💤  - 3  0 ❌ ±0  1 🔥 +1 
16 704 runs   - 37  16 564 ✅  - 35  139 💤  - 3  0 ❌ ±0  1 🔥 +1 

For more details on these errors, see this check.

Results for commit b440e89. ± Comparison against base commit 51fed8e.

This pull request removes 37 tests.

AllWin32Tests org.eclipse.swt.graphics.ImageWin32Tests ‑ testImageDataForDifferentFractionalZoomsShouldBeDifferent
AllWin32Tests org.eclipse.swt.graphics.ImageWin32Tests ‑ testImageShouldHaveDimesionAsPerZoomLevel
AllWin32Tests org.eclipse.swt.tests.win32.Test_org_eclipse_swt_dnd_DND ‑ testByteArrayTransfer
AllWin32Tests org.eclipse.swt.tests.win32.Test_org_eclipse_swt_dnd_DND ‑ testFileTransfer
AllWin32Tests org.eclipse.swt.tests.win32.Test_org_eclipse_swt_dnd_DND ‑ testHtmlTransfer
AllWin32Tests org.eclipse.swt.tests.win32.Test_org_eclipse_swt_dnd_DND ‑ testImageTransfer_fromCopiedImage
AllWin32Tests org.eclipse.swt.tests.win32.Test_org_eclipse_swt_dnd_DND ‑ testImageTransfer_fromImage
AllWin32Tests org.eclipse.swt.tests.win32.Test_org_eclipse_swt_dnd_DND ‑ testImageTransfer_fromImageData
AllWin32Tests org.eclipse.swt.tests.win32.Test_org_eclipse_swt_dnd_DND ‑ testImageTransfer_fromImageDataFromImage
AllWin32Tests org.eclipse.swt.tests.win32.Test_org_eclipse_swt_dnd_DND ‑ testRtfTransfer
…

♻️ This comment has been updated with latest results.

[fedejeanne]

LGTM but since this is for Mac, I'd like a second opinion. @BeckerWdf ?

[BeckerWdf]

LGTM but since this is for Mac, I'd like a second opinion. @BeckerWdf ?

What exactly should I comment on? Should I test the change? If yes: How can I test this?

[fedejeanne]

LGTM but since this is for Mac, I'd like a second opinion. @BeckerWdf ?

What exactly should I comment on? Should I test the change? If yes: How can I test this?

This PR brings no functional changes with it, it is merely a refactoring. The test consists in running Eclipse performing any action (open a view, edit something, drag stuff around) that runs through the changed method and check that it behaves as it did before.

Since this is done in the context of monitors and zooms, you should try it with different zoom levels. The best way is to have 2 monitors with different zooms and test the same things moving the Workbench/Views between the monitors but if you only have 1 monitor, you could simply try by changing the zoom level between operations.

Usually, this kind of testing can be done in no more than 10 minutes :-)

Thank you!

[fedejeanne]

Thank you for reviewing!

The failing check is unrelated (a test failure on a previous run: #2098)