1315477 - Eliminate static_cast<>s on LayerManager types

Status: RESOLVED FIXED

(Core :: Graphics: WebRender, defect)

Description

[Kartikaya Gupta (email:[e-mail]) (away until Feb-2020)]

In a number of places we do a static_cast<ClientLayerManager*> on a manager. All of these seem to be guarded by checks of the backend type being equal to LAYERS_CLIENT. However it's better to just do manager->AsClientLayerManager() which effectively does the same thing, and returns null if not.

There is at least one place [1] where we assume that a layer manager in the content process that's not a LAYERS_CLIENT *must* be a BasicLayerManager, and does a static_cast to that effect at [2]. Of course, if we're using something like a WebRenderLayerManager that just writes all over the WRLM and corrupts the state.

[1] http://searchfox.org/mozilla-central/rev/f5c9e9a249637c9abd88754c8963ecb3838475cb/widget/PuppetWidget.cpp#1082
[2] http://searchfox.org/mozilla-central/rev/f5c9e9a249637c9abd88754c8963ecb3838475cb/widget/nsBaseWidget.cpp#909

Comment 1

[Kartikaya Gupta (email:[e-mail]) (away until Feb-2020)]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=03c0a547128429b8f4bd0436bc3195cc1e45c86a

Comment 2

[Kartikaya Gupta (email:[e-mail]) (away until Feb-2020)]

Attachment: Bug 1315477 - Remove some instances of static_cast'ing to ClientLayerManager.

Review commit: https://reviewboard.mozilla.org/r/91072/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/91072/

Comment 3

[Kartikaya Gupta (email:[e-mail]) (away until Feb-2020)]

Attachment: Bug 1315477 - Add a AsBasicLayerManager() function and use instead of static_casts.

Review commit: https://reviewboard.mozilla.org/r/91074/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/91074/

Comment 4

[Matt Woodrow (:mattwoodrow)]

Comment on attachment 8808226 [details]
Bug 1315477 - Add a AsBasicLayerManager() function and use instead of static_casts.

https://reviewboard.mozilla.org/r/91074/#review90926

Comment 5

[Matt Woodrow (:mattwoodrow)]

Comment on attachment 8808225 [details]
Bug 1315477 - Remove some instances of static_cast'ing to ClientLayerManager.

https://reviewboard.mozilla.org/r/91072/#review90930

Comment 6

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/9f208d6e52c5
Remove some instances of static_cast'ing to ClientLayerManager. r=mattwoodrow
https://hg.mozilla.org/integration/autoland/rev/a229fb665939
Add a AsBasicLayerManager() function and use instead of static_casts. r=mattwoodrow

Comment 7

[Wes Kocher (:KWierso)]

https://hg.mozilla.org/mozilla-central/rev/9f208d6e52c5
https://hg.mozilla.org/mozilla-central/rev/a229fb665939