4249 [webview] Fix typos in the README (cla: yes, waiting for tree to go green, p: webview_flutter, last mile)

4250 Fix crash from null Google Maps object (cla: yes, waiting for tree to go green, p: google_maps_flutter, platform-android)

4251 [google_sign_in] adds option to re-authenticate on google silent sign in (cla: yes, waiting for tree to go green, p: google_sign_in)

4256 [camera] Expand CameraImage DTO with properties for lens aperture, exposure time and ISO.  (cla: yes, waiting for tree to go green, p: camera, platform-ios, platform-android)

4258 [camera] Add Android & iOS implementations for pausing the camera preview  (cla: yes, waiting for tree to go green, p: camera, platform-ios, platform-android)