android_webview: conditionally include android_webview_tests to fix downstream build breakage

BUG=

NOTRY=true

Review URL: https://codereview.chromium.org/46453002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@231179 0039d316-1c4b-4281-b951-d872f2087c98
Fix Telemetry.

"Introduce DevToolsTargetImpl" breaks Telemetry because it no longer returns
type: "other" for prerenders. "Add URL query parameter" had to go because it
builds atop the broken change.

BUG=311652
TBR=kaznacheev@chromium.org
NOTRY=True

Revert "DevTools: Add URL query parameter to json/new command"

This reverts commit 296d770a744a554751bca5bdf16e681bb8615589.

Revert "DevTools: Introduce DevToolsTargetImpl to unify debug target across several places in Chrome"

This reverts commit 329082e9edfe5a0e5672250abc269a66ba33bdf1.

Review URL: https://codereview.chromium.org/46523002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@231180 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 231180