'static const' means, there must be at most one of these, and initialize it at
compile time if possible or runtime if necessary. This leads to unexpected
code execution, and TSAN* will complain about races on the guard variables.
Generally 'constexpr' or 'const' are better choices. Neither can cause races:
they're either intialized at compile time (constexpr) or intialized each time
independently (const).
This CL prefers constexpr where possible, and uses const where not. It even
prefers constexpr over const where they don't make a difference... I want to have
lots of examples of constexpr for people to see and mimic.
The scoped-to-class static has nothing to do with any of this, and is not changed.
* Not yet on the bots, which use an older TSAN.
BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2300623005
Review-Url: https://codereview.chromium.org/2300623005
Currently, the tile offset is added when drawing the picture. This might
have made a tiny bit of sense when the picture was always positioned at
origin, but with a picture cull rect offset things looks really strange.
For example, to specify a tile == the picture cull rect we have to pass
in [-cullrect.x, -cullrect.y, cullrect.width, cullrect.height]. Yikes.
(there's also a bug when not passing a tile, as we use a default tile
== cullrect but don't compensate for the above oddity)
This changes the semantics of the tile offset: it is now subtracted when
drawing the picture tile. As a consequence, one can pass in a tile equal
to the cull rect and get the expected behavior (same when not passing
a tile).
This will require a minor Blink change with the roll, as one client
works around the current behavior:
https://codereview.chromium.org/789503003R=reed@google.com,robertphillips@google.com
BUG=440046
Review URL: https://codereview.chromium.org/733203005
