DevTools: Use role=textbox for the InplaceEditor
DevTools: Use role=textbox for the InplaceEditor

Change-Id: I52f28ee062a9f651dbb0e95f6abeb762b6afab35
Reviewed-on: https://chromium-review.googlesource.com/1229673
Reviewed-by: Erik Luo <26192f5e05d23e5ee959014fb911d780e566545b@chromium.org>
Commit-Queue: Joel Einbinder <bab755abe9fee48fe544272e55f73517d4e4a725@chromium.org>
Cr-Original-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#592240}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: e56c3ed2bce82de64cd6b4e2931513ff3ca79c16
ChromeDevTools/devtools-frontend,ChromeDevTools/devtools-frontend,ChromeDevTools/devtools-frontend,dart-archive/devtools-frontend,ChromeDevTools/devtools-frontend,dart-archive/devtools-frontend,ChromeDevTools/devtools-frontend,dart-archive/devtools-frontend,dart-archive/devtools-frontend,dart-archive/devtools-frontend,dart-archive/devtools-frontend,ChromeDevTools/devtools-frontend