compositing: Fix a couple of bugs that prevented iframes from painting after navigation.
The first bug was that iframes were not reflowed in their parent DOM when the child page navigated. This is fixed by simply having the constellation notify the appropriate script thread when navigation occurs.
The second bug was that the compositor was unable to adjust the pipeline for existing iframe layers, only new ones. This patch adds logic to do that.
The third bug was that we have ad-hoc reflow calls throughout script/, and we didn't trigger any reflow from the code that dispatches the `load` event for the iframe so the test for the first two issues would always time out. The second commit adds another reflow call to do that, and also bites the bullet and adds a catch-all reflow (which does nothing if there's no dirty nodes in the document) at the return to the event loop.
Closes#8081.
Extension of #9285.
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after navigation.
The first bug was that iframes were not reflowed in their parent DOM
when the child page navigated. This is fixed by simply having the
constellation notify the appropriate script thread when navigation
occurs.
The second bug was that the compositor was unable to adjust the pipeline
for existing iframe layers, only new ones. This patch adds logic to do
that.
Closes#8081.
absolutely-positioned flows separately when storing overflow.
This code dates back to the time when absolutely positioned flows were
ignored by all of their ancestors up to the containing block. This
hasn't been true for at least a year.
Closes#9306.
Closes#9309.
Is a partial fix for #9308.
Test redirect_count boundaries in Fetch
I've written two new tests for Fetch: one to test the highest possible number of redirects succeeds; and another to ensure a failure in Fetch by requesting too many redirects. I also wrote a helper function to be used by each test, since the main difference is how many times they try to redirect.
I've also changed the check against redirect_count in http_network fetch to compare it as greater than or equal to 20, as opposed to being only equal to 20. That's outside of the spec, but in my experience testing for pure equality can easily create errors. Even though it's technically not possible for redirect_count be above 20, bizarre bugs during runtime certainly happen.
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Implement a basic test for Fetch
As per @jdm's suggestion that I start minimally testing the Fetch protocol to catch any errors, I wrote a very simple test that just calls Fetch and checks that the response isn't a network error. I've made changes as necessary for every failure I encountered, although this doesn't mean the implementation is faultless yet.
As always, I look forward to any feedback for improvements regarding the test itself, the changes to the fetch files I've made, and anything that I missed and should update.
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