Support line-height in geckolib

[mbrubeck]

r? @bholley

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This change is

[highfive]

Heads up! This PR modifies the following files:

• @bholley: components/style/properties/longhand/inherited_text.mako.rs

[highfive]

Warning

• These commits modify unsafe code. Please review it carefully!
• These commits modify style code, but no tests are modified. Please consider adding a test!

[bholley]

I need to start culling stuff before PTO. @heycam can you review?

[mbrubeck]

@bors-servo delegate=heycam

[bors-servo]

✌️ @heycam can now approve this pull request

[emilio]

r=me with that question answered/nit addressed if needed.

-S-awaiting-review +S-awaiting-answer

Previously, bors-servo wrote…

✌️ @heycam can now approve this pull request

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Reviewed 3 of 3 files at r1.
Review status: all files reviewed at latest revision, 2 unresolved discussions.

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components/style/properties/longhand/inherited_text.mako.rs, line 18 [r1] (raw file):

    pub enum SpecifiedValue {
        Normal,
        % if product == "gecko":

Well, I can't say I really like this, but I can't think of anything better without introducing yet another generic type around, so...

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ports/geckolib/properties.mako.rs, line 741 [r1] (raw file):

    fn copy_line_height_from(&mut self, other: &Self) {
        debug_assert_unit_is_safe_to_copy(self.gecko.mLineHeight.mUnit);
        self.gecko.mLineHeight.mUnit = other.gecko.mLineHeight.mUnit;

Hum... can't you do self.gecko.mLineHeight = other.gecko.mLineHeight?

If you can't maybe this should be a good thing to factor out (though if it's just used here and you want to land it it's fine for me).

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Comments from Reviewable

[highfive]

New code was committed to pull request.

[mbrubeck]

@bors-servo r=emilio

Hum... can't you do self.gecko.mLineHeight = other.gecko.mLineHeight?

If you can't maybe this should be a good thing to factor out (though if it's just used here and you want to land it it's fine for me).

We can't do that because nsStyleCoord isn't Copy. We can't just implement Copy or Clone and then reassign, because we also need to check whether it's refcounted. Long-term we can implement refcounting using Clone and Drop. For new I factored out the debug assertion into a new method.

[bors-servo]

📌 Commit cc4309d has been approved by emilio

[bors-servo]

⌛ Testing commit cc4309d with merge 8cc8395...

[bors-servo]

💔 Test failed - linux-rel

[highfive]

  ▶ TIMEOUT [expected PASS] /css21_dev/html4/text-transform-capitalize-001.htm
  │ 
  │ Xlib:  extension "XFree86-VidModeExtension" missing on display ":0".
  │ Shutting down the Constellation after generating an output file or exit flag specified
  │ thread 'Constellation' panicked at 'Couldn't receive FontCacheThread reply: IoError(Error { repr: Os { code: 104, message: "Connection reset by peer" } })', ../src/libcore/result.rs:785
  │ stack backtrace:
  │    1:     0x7fad77d934e0 - std::sys::backtrace::tracing::imp::write::h9fb600083204ae7f
  │    2:     0x7fad77d9b10b - std::panicking::default_hook::_$u7b$$u7b$closure$u7d$$u7d$::hca543c34f11229ac
  │    3:     0x7fad77d9ad73 - std::panicking::default_hook::hc2c969e7453d080c
  │    4:     0x7fad77a17767 - util::panicking::initiate_panic_hook::_$u7b$$u7b$closure$u7d$$u7d$::_$u7b$$u7b$closure$u7d$$u7d$::he2b22674ad1748f3
  │    5:     0x7fad77d810cc - std::panicking::rust_panic_with_hook::hfe203e3083c2b544
  │    6:     0x7fad77d9b351 - std::panicking::begin_panic::h4889569716505182
  │    7:     0x7fad77d82b2a - std::panicking::begin_panic_fmt::h484cd47786497f03
  │    8:     0x7fad77d9b2ee - rust_begin_unwind
  │    9:     0x7fad77dd18ef - core::panicking::panic_fmt::h257ceb0aa351d801
  │   10:     0x7fad775fa193 - core::result::unwrap_failed::h1d94443d858a91df
  │   11:     0x7fad77620d7a - gfx::font_cache_thread::FontCacheThread::exit::h335f05e55068200a
  │   12:     0x7fad7626deea - _<constellation..constellation..Constellation<Message, LTF, STF>>::handle_request_from_compositor::h36aa44f58af516a2
  │   13:     0x7fad7625ae84 - _<constellation..constellation..Constellation<Message, LTF, STF>>::handle_request::hcce69aee4a14205a
  │   14:     0x7fad7624d76c - std::panicking::try::call::h22909ee1e8b98df9
  │   15:     0x7fad77da554b - __rust_try
  │   16:     0x7fad77da54ee - __rust_maybe_catch_panic
  │   17:     0x7fad7624eec5 - _<F as alloc..boxed..FnBox<A>>::call_box::h11cfda0b44685af6
  │   18:     0x7fad77d994f4 - std::sys::thread::Thread::new::thread_start::h6f266e069bf4ec2b
  │   19:     0x7fad73c55181 - start_thread
  │   20:     0x7fad7376c47c - __clone
  └   21:                0x0 - <unknown>

[jdm]

@bors-servo: retry

• #8815

[bors-servo]

⌛ Testing commit cc4309d with merge 6ef0423...

[bors-servo]

💔 Test failed - arm32

[emilio]

@bors-servo: retry

• git

[bors-servo]

⌛ Testing commit cc4309d with merge 8caa17a...

[bors-servo]

☀️ Test successful - android, arm32, arm64, linux-dev, linux-rel, mac-dev-unit, mac-rel-css, mac-rel-wpt, windows