Fix MSVC 14.29 errors:

- It doens't know which operator == to use when there is using
 EnumClassBitmask that looks like (a & b) == 0. Instead use just
 the form (a & b).
 - It doesn't do automatic capture of constexpr variables in lambdas so
 turn a couple constexpr into regular const.
 - It (correctly) warns that if constexpr (std::is_constant_evaluated())
 is always true, so remove the constexpr keyword.

 Bug: None

Change-Id: If7857abd1c30acb0736557844ff13f32a19d54cf
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/117888
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Ben Clayton <bclayton@google.com>
Kokoro: Corentin Wallez <cwallez@chromium.org>

src/dawn/native/opengl/TextureGL.cpp

@@ -246,7 +246,7 @@ MaybeError Texture::ClearTexture(const SubresourceRange& range,
     float fClearColor = (clearValue == TextureBase::ClearValue::Zero) ? 0.f : 1.f;
 
     if (GetFormat().isRenderable) {
-        if ((range.aspects & (Aspect::Depth | Aspect::Stencil)) != 0) {
+        if (range.aspects & (Aspect::Depth | Aspect::Stencil)) {
             GLfloat depth = fClearColor;
             GLint stencil = clearColor;
             if (range.aspects & Aspect::Depth) {