Frame identifiers have changed from int64_t to string type. This is due
to https://crbug.com/1502660 which removes access to frame routing IDs
in the renderer process. New cross-process frame identifiers are 160-bit
values (32-bit child process ID + 128-bit local frame token) and most
easily represented as strings. All other frame-related expectations and
behaviors remain the same.
This change moves the SendProcessMessage method from CefBrowser to CefFrame and
adds CefBrowser parameters to OnProcessMessageReceived and
OnDraggableRegionsChanged.
The internal implementation has changed as follows:
- Frame IDs are now a 64-bit combination of the 32-bit render_process_id and
render_routing_id values that uniquely identify a RenderFrameHost (RFH).
- CefFrameHostImpl objects are now managed by CefBrowserInfo with life span tied
to RFH expectations. Specifically, a CefFrameHostImpl object representing a
sub-frame will be created when a RenderFrame is created in the renderer
process and detached when the associated RenderFrame is deleted or the
renderer process in which it runs has died.
- The CefFrameHostImpl object representing the main frame will always be valid
but the underlying RFH (and associated frame ID) may change over time as a
result of cross-origin navigations. Despite these changes calling LoadURL on
the main frame object in the browser process will always navigate as expected.
- Speculative RFHs, which may be created as a result of a cross-origin
navigation and discarded if that navigation is not committed, are now handled
correctly (e.g. ignored in most cases until they're committed).
- It is less likely, but still possible, to receive a CefFrame object with an
invalid frame ID (ID < 0). This can happen in cases where a RFH has not yet
been created for a sub-frame. For example, when OnBeforeBrowse is called
before initiating navigation in a previously nonexisting sub-frame.
To test: All tests pass with NetworkService enabled and disabled.