Also makes the toolbar unclickable so it can't be switching into
edit mode, and removes all other actions.
Moved the custom tab back button bitmap checking to the feature from the
CustomTabConfig since we needed to know the DisplayMetrics for the
current screen to properly compare it to the max dp value.
Android doesn't kill the process immediately after all foreground activities are gone. So we still have
time to save the state from our background thread.
This also avoids ANRs and issues we saw related to blocking the UI thread, e.g.:
https://github.com/mozilla-mobile/reference-browser/issues/405
- Remove a few unnecessary dependencies
- Add some comments around usage of 'api'
- Mark some of the dependencies as 'api' if they're necessary for use of the module
The main change here is that EngineSessionHolder can now hold an EngineState and this state
is used when we need to create an EngineSession (which will clear the state). This has the
following advantages:
* When restoring we can just attach the EngineState and do not need to create the
EngineSession immediately. With that we do not load all the EngineSessions and everything
at once. Initially only the selected EngineSession will be created and loaded. That will
make the restore faster and use less resources when restoring a lot of sessions.
* (Not in this commit, for a follow-up) It allows us to close EngineSession instances and
just keep the EngineState around until we need the EngineSession again. That's something
we could do in low memory situations or when there are just too many sessions/tabs open
to be performant (e.g. only keep the last recently used EngineSession instances around).
Current storage format doesn't preserve session order, and snapshot processing
is a bit vague around the various edge cases.
This patch changes the storage format to use an ordered list (vs a set), and firms
up creation, processing and restoration of snapshots. Guiding principles are:
- be explicit,
- be lenient about what we accept, and strict about what we produce.
Storage format version isn't bumped out of simplicity: there are no production
consumers of this (that we know of) that we'll need to migrate, and so let's
do the simple thing this time.
This patch introduces an idea of a SessionsSnapshot, which is a representation of
SessionManager's state that's suitable for persistance. SessionStorage's APIs read/write
APIs are changed to operate over the snapshot.
A public `restore` method was added to SessionManager, along with onSessionsRestored observer method,
which allow restoring a SessionsSnapshot.
When creating new session from an existing session, we need to the
relationship between two sessions. For example, to click a href link in
web-page to open new tab.
This commit add parent id to Session. If a session is added without
parent, it will be append to tail of sessions. Otherwise it will sit
next to parent.
Problem this is trying to solve:
SessionManager doesn't own its "empty" state (no selected session, no sessions at all).
Components which rely on the SessionManager may make assumptions about what happens
when SessionManager becomes "empty", and current approach is for some component to "take charge",
and be responsible for adding a "default" session when there are none left.
This doesn't bode well for composing components. We can get into a kind of "action at a distance"
situation, when various components make certain assumptions (say, SessionManager must always have
a selected session), but none of them actually take charge and populate the manager when appropriate.
Since components aren't necessarily aware of each other, and ideally are arbitrarily composable,
this graph of implicit dependencies becomes problematic.
This patch:
A naive solution to this is to get the SessionManager to owner its "empty" state.
This patch allows "default" behaviour to be specified at creation time, supplying a lambda
which produces a default session. Not supplying this lambda is equivalent to allowing SessionManager
to be empty.
Fixes https://github.com/mozilla-mobile/android-components/issues/764.
