Clarify JavaDoc of WebSettings.setAllowFileAccessFromFileURLs.

According to CTS tests (WebSettingsTest.testLocalImageLoads),
local images access is allowed regardless of the state of
AllowFileAccessFromFileURLs.

Bug: 5461416

Change-Id: I71f5c38a6b0f3720c8c369c0e19f379c78ace06f
1 file changed