This is a rollup of the following patches
Bug 811315, part 0.9: Fix pre-existing race condition that allows dying ContentParents to accidentally try to load new TabParents. r=jlebar
Bug 811315, part 0.91: Fix another pre-existing race condition where FirstIdle might run after ContentChild::ActorDestroy(). r=jlebar
Bug 811315, part 1: Make "browser" process limit infinite and unload the processes when all tabs are closed. Firefox with process-per-tab! r=jlebar
Bug 811315, part 2: Pass scrolling-behavior hint down into TabParent instead of inferring it from app/browser. r=jlebar
Bug 811315, part 3: Add a mozasyncpanzoom attribute for iframes and honor it when constructing a remote frame. r=jlebar sr=roc
The main bug fixed here is that in half of our interfaces, we use "is browser frame/element" to mean "browser or app", and in the other half, we use it to mean "is browser not app".
There's a related, functional bug also fixed here, which is that a browser process doesn't inherit its parent's app-id. This causes problems e.g. for IndexedDB: If a browser inside an app uses IndexedDB, the DB should have the app's app-id.
I also modified Tab{Parent,Child} and nsFrameLoader to call "app" "ownOrContainingApp", to emphasize that we might have inherited the app from a parent process. I left nsIDocShell::appId alone, because changing that would have necessitated changing nsILoadGroup and therefore a /lot/ of users in Necko; it's also not clear it would have clarified anything in those cases.
The main bug fixed here is that in half of our interfaces, we use "is browser frame/element" to mean "browser or app", and in the other half, we use it to mean "is browser not app".
There's a related, functional bug also fixed here, which is that a browser process doesn't inherit its parent's app-id. This causes problems e.g. for IndexedDB: If a browser inside an app uses IndexedDB, the DB should have the app's app-id.
I also modified Tab{Parent,Child} and nsFrameLoader to call "app" "ownOrContainingApp", to emphasize that we might have inherited the app from a parent process. I left nsIDocShell::appId alone, because changing that would have necessitated changing nsILoadGroup and therefore a /lot/ of users in Necko; it's also not clear it would have clarified anything in those cases.
