• Andreas Haas's avatar
    [api] Add callback to set up conditional features · 16d9298a
    Andreas Haas authored
    Origin trials allow webpages to use experimental features even though
    the features are not yet enabled by default. These features will then
    get enabled per execution context: it is possible that the feature is
    enabled in one execution context but disabled in another execution
    context. In V8 we check for origin trials by calling a callback provided
    by the embedder that takes the context as a parameter and returns
    whether a feature is enabled in this context or not.
    
    This approach fails when a feature changes the context itself, e.g. by
    extending the global object. In that case the context is not available
    yet to check for the origin trial.
    
    To solve the problem this CL adds a new API function that can be called
    by the embedder to notify V8 that context with the origin trial
    information is finished. After that V8 can read the origin trial
    information from the context and extend e.g. the global object with the
    origin trial features.
    
    Additionally to the API this CL also adds code to enable the
    WebAssembly.Exception constructor conditionally, depending on whether
    it has been enabled by an origin trial or not.
    
    The Blink-side change: https://crrev.com/c/2775573
    
    R=ulan@chromium.org, jkummerow@chromium.org
    
    Change-Id: Ic05c4a89eb3e0e31469e49da8767d630c43b2e00
    Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2773287Reviewed-by: 's avatarAndreas Haas <ahaas@chromium.org>
    Reviewed-by: 's avatarUlan Degenbaev <ulan@chromium.org>
    Reviewed-by: 's avatarJakob Kummerow <jkummerow@chromium.org>
    Commit-Queue: Andreas Haas <ahaas@chromium.org>
    Cr-Commit-Position: refs/heads/master@{#73597}
    16d9298a
api.cc 387 KB