WebView2: Add JS API docs for WebViewMessageEvent and cancelPromise

[peiche-jessica]

Rendered webpages for review:

• WebView2Script package (root)
  • https://review.learn.microsoft.com/microsoft-edge/webview2/reference/javascript/index?branch=pr-en-us-3110
  • Before/Live
• WebViewMessageEvent interface (new webpage)
  • https://review.learn.microsoft.com/microsoft-edge/webview2/reference/javascript/webviewmessageevent?branch=pr-en-us-3110
• WebViewEventMap interface (new webpage)
  • https://review.learn.microsoft.com/microsoft-edge/webview2/reference/javascript/webvieweventmap?branch=pr-en-us-3110
• HostObjectsAsyncRoot class > cancelPromise(promise) (new section in webpage)
  • https://review.learn.microsoft.com/microsoft-edge/webview2/reference/javascript/hostobjectsasyncroot?branch=pr-en-us-3110#webview2script-hostobjectsasyncroot-cancelpromise-member(1)
  • Before/Live

AB#49581036

[learn-build-service-prod[bot]]

Learn Build status updates of commit e7fd765:

:warning: Validation status: warnings

File	Status	Preview URL	Details
microsoft-edge/webview2/reference/javascript/webviewmessageevent.yml	:warning:Warning	View	Details
microsoft-edge/webview2/reference/javascript/hostobjectsasyncroot.yml	:white_check_mark:Succeeded	View
microsoft-edge/webview2/reference/javascript/index.yml	:white_check_mark:Succeeded	View
microsoft-edge/webview2/reference/javascript/webvieweventmap.yml	:white_check_mark:Succeeded	View

microsoft-edge/webview2/reference/javascript/webviewmessageevent.yml

• Line 43, Column 15: [Warning: xref-not-found - See documentation] Cross reference not found: 'WebView2Script!WebView:interface'.

For more details, please refer to the build report.

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[learn-build-service-prod[bot]]

Learn Build status updates of commit 034897f:

:white_check_mark: Validation status: passed

File	Status	Preview URL	Details
microsoft-edge/webview2/reference/javascript/hostobjectsasyncroot.yml	:white_check_mark:Succeeded	View
microsoft-edge/webview2/reference/javascript/index.yml	:white_check_mark:Succeeded	View
microsoft-edge/webview2/reference/javascript/webvieweventmap.yml	:white_check_mark:Succeeded	View
microsoft-edge/webview2/reference/javascript/webviewmessageevent.yml	:white_check_mark:Succeeded	View

For more details, please refer to the build report.

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[learn-build-service-prod[bot]]

Learn Build status updates of commit bc27f9e:

:white_check_mark: Validation status: passed

File	Status	Preview URL	Details
microsoft-edge/webview2/reference/javascript/hostobjectsasyncroot.yml	:white_check_mark:Succeeded	View
microsoft-edge/webview2/reference/javascript/index.yml	:white_check_mark:Succeeded	View
microsoft-edge/webview2/reference/javascript/webvieweventmap.yml	:white_check_mark:Succeeded	View
microsoft-edge/webview2/reference/javascript/webviewmessageevent.yml	:white_check_mark:Succeeded	View

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[learn-build-service-prod[bot]]

Learn Build status updates of commit 9e7dbc2:

:white_check_mark: Validation status: passed

File	Status	Preview URL	Details
microsoft-edge/webview2/reference/javascript/hostobjectsasyncroot.yml	:white_check_mark:Succeeded	View
microsoft-edge/webview2/reference/javascript/index.yml	:white_check_mark:Succeeded	View
microsoft-edge/webview2/reference/javascript/webvieweventmap.yml	:white_check_mark:Succeeded	View
microsoft-edge/webview2/reference/javascript/webviewmessageevent.yml	:white_check_mark:Succeeded	View

For more details, please refer to the build report.

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[learn-build-service-prod[bot]]

Learn Build status updates of commit 5a51545:

:white_check_mark: Validation status: passed

File	Status	Preview URL	Details
microsoft-edge/toc.yml	:white_check_mark:Succeeded	View
microsoft-edge/webview2/reference/javascript/hostobjectsasyncroot.yml	:white_check_mark:Succeeded	View
microsoft-edge/webview2/reference/javascript/index.yml	:white_check_mark:Succeeded	View
microsoft-edge/webview2/reference/javascript/webvieweventmap.yml	:white_check_mark:Succeeded	View
microsoft-edge/webview2/reference/javascript/webviewmessageevent.yml	:white_check_mark:Succeeded	View

For more details, please refer to the build report.

For any questions, please:

• Try searching the learn.microsoft.com contributor guides
• Post your question in the Learn support channel