Auto merge of #16034 - jonathandturner:fix_font, r=metajack

Fix Windows UI and font squishing

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This PR:

* updates the browserhtml dep (fixes https://github.com/servo/servo/issues/15255)
* updates the Windows font metric calculation (fixes https://github.com/servo/servo/issues/15698, based on codec-abc https://github.com/servo/servo/pull/15937#issuecomment-286513712)
* may address https://github.com/servo/servo/issues/15933.  With this PR, I was not able to repro

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #__ (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [X] These changes do not require tests because change are to UI/visual results of font drawing

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components/gfx/platform/windows/font.rs

@@ -372,7 +372,7 @@ impl FontHandleMethods for FontHandle {
             descent:          au_from_du_s(dm.descent as i32),
             max_advance:      au_from_pt(0.0), // FIXME
             average_advance:  au_from_pt(0.0), // FIXME
-            line_gap:         au_from_du(dm.lineGap as i32),
+            line_gap:         au_from_du((dm.ascent + dm.descent + dm.lineGap as u16) as i32),
         };
         debug!("Font metrics (@{} pt): {:?}", self.em_size * 12., metrics);
         metrics