Save search term in Search panel on keydown rather than on enter.
Save search term in Search panel on keydown rather than on enter.

R=68542faf32f0a558a873c0f094ca9bedb2744bff@chromium.org

Fixed:1155532
Change-Id: Ief28415a14bd56e30db059bc78349cd494d26a69
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/2577568
Commit-Queue: Changhao Han <68542faf32f0a558a873c0f094ca9bedb2744bff@chromium.org>
Auto-Submit: Yang Guo <1cf0af8245a3a17a632a2c73531392b0f9761c76@chromium.org>
Reviewed-by: Changhao Han <68542faf32f0a558a873c0f094ca9bedb2744bff@chromium.org>

ChromeDevTools/devtools-frontend,ChromeDevTools/devtools-frontend,ChromeDevTools/devtools-frontend,ChromeDevTools/devtools-frontend,ChromeDevTools/devtools-frontend,ChromeDevTools/devtools-frontend