Accept more MIME types in copies from wayland clients to chrome

Currently we only accept UTF-8 plain text. This CL expands the range
of accepted types to "text/plain", "text/html" (in any character set),
"text/rtf", and any image subtype listed in
//third_party/blink/common/mime_util/ as a supported image

Bug: 809898
Change-Id: If15fb3adbcb97f7a85d445f74dae391845b5e3ab
Reviewed-by: Philip Rogers <>
Reviewed-by: Matt Mueller <>
Reviewed-by: Mitsuru Oshima <>
Reviewed-by: Robert Sesek <>
Reviewed-by: Ken Rockot <>
Commit-Queue: Fergus Dall <>
Cr-Commit-Position: refs/heads/master@{#660275}
11 files changed