[MediaCapabilities] Protect MediaCapabilities JS wrapper from GC#1678
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asurdej-comcast wants to merge 1 commit into
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[MediaCapabilities] Protect MediaCapabilities JS wrapper from GC#1678asurdej-comcast wants to merge 1 commit into
asurdej-comcast wants to merge 1 commit into
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Add GenerateIsReachable=ReachableFromNavigator to prevent wrapper GC. The MediaCapabilities interface is annotated [SameObject] in the spec, meaning navigator.mediaCapabilities must return the same object on every access. Without GC protection, the JS wrapper can be collected when no JS reference holds it, causing a new wrapper to be created on next access. This breaks object identity and loses any user-set properties.
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Add GenerateIsReachable=ReachableFromNavigator to prevent wrapper GC. The MediaCapabilities interface is annotated [SameObject] in the spec, meaning navigator.mediaCapabilities must return the same object on every access. Without GC protection, the JS wrapper can be collected when no JS reference holds it, causing a new wrapper to be created on next access. This breaks object identity and loses any user-set properties.
This fixes an issue with ShakaPlayer that sets its own, custom navigator.mediaCapabilities.decodingInfo wrapper JS function that provides DRM data in addition to native decodingInfo impl.
See https://github.com/shaka-project/shaka-player/blob/ce7ee4b76f1fd6104519fe6f20fe7dda9d759eaf/lib/polyfill/mcap_encryption_scheme.js#L131
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