Revert "Hide SkEncodedInfo"

This reverts commit c6f7a4ffa9522159efc42f7c948bba5e66bb8844.

Reason for revert: Causing differences in Gold, stemming from the fact that this changes the recommended SkImageInfo for 16 bits-per-component PNG from N32 to F16.
- an F16 bitmap already png-encodes to a 16 bits-per-component PNG, but it does not encode a linear colorspace (possibly a bug?). when we decode this PNG using getInfo(), it fails because it has an F16 color type and non-linear colorspace. (In the encode-srgb-png gm, this results in blank results for F16.) We could correct this on the encoder side, but it seems possible that a 16 bits-per-component PNG could be encoded with a different color space. In that case, we'd want SkCodec to recommend F16/SRGBLinear, but I think we'd want the SkCodec to store the encoded SkColorSpace so that we can Xform between the two. Currently SkCodec only stores one color space, so that will require a refactor.
- When decoding 16-bits-per-component PNGs, we are now decoding them to F16. This shows differences in Gold. The srgb/gpu results now look more like F16. I think this is fine.

Original change's description:
> Hide SkEncodedInfo
> 
> Bug: skia:7353
> Bug: skia:6839
> 
> This contains information that is not necessary for clients to know. The
> Color enum tells the number of components in the input, but this is only
> interesting internally (to the SkSwizzler).
> 
> Similarly, the Alpha enum differs from SkAlphaType in that it has
> kBinary instead of kPremul. This is useful information only internally
> for determining whether the SkColorSpaceXform needs to premultiply.
> 
> The bitsPerComponent is potentially useful for a client; Android (in
> SkAndroidCodec) uses it to determine the SkColorType. Rather than
> exposing bitsPerComponent, use it to make the same decision that Android
> would have made - 16 bits per component means to set the info to F16. Add
> a test that computeOutputColorType behaves as expected.
> 
> Switch conversionSupported to use an SkColorType, which is enough info.
> 
> Replace the SkEncodedInfo::Alpha field on SkCodec::FrameInfo with an
> SkAlphaType.
> 
> SkCodec still needs an SkEncodedInfo, so move its header (which is
> already not SK_API) to include/private.
> 
> Change-Id: Ie2cf11339bf999ebfd4390c0f448f7edd6feabda
> Reviewed-on: https://skia-review.googlesource.com/79260
> Reviewed-by: Mike Reed <reed@google.com>
> Reviewed-by: Mike Klein <mtklein@chromium.org>
> Commit-Queue: Leon Scroggins <scroggo@google.com>

TBR=mtklein@chromium.org,scroggo@google.com,reed@google.com

Change-Id: I0c5dd1461e1b70d1e55349a8e7ee6b029c3f556e
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: skia:7353, skia:6839
Reviewed-on: https://skia-review.googlesource.com/80660
Reviewed-by: Leon Scroggins <scroggo@google.com>
Commit-Queue: Leon Scroggins <scroggo@google.com>

2 files changed, 4 insertions, 5 deletions

diff --git a/third_party/gif/SkGifImageReader.cpp b/third_party/gif/SkGifImageReader.cpp
index a04f8e11d0..a54fb59d3b 100644
--- a/third_party/gif/SkGifImageReader.cpp
+++ b/third_party/gif/SkGifImageReader.cpp
@@ -879,16 +879,15 @@ static bool restore_bg(const SkFrame& frame) {
     return frame.getDisposalMethod() == SkCodecAnimation::DisposalMethod::kRestoreBGColor;
 }
 
-SkEncodedInfo::Alpha SkGIFFrameContext::onReportedAlpha() const {
+bool SkGIFFrameContext::onReportsAlpha() const {
     // Note: We could correct these after decoding - i.e. some frames may turn out to be
     // independent and opaque if they do not use the transparent pixel, but that would require
     // checking whether each pixel used the transparent index.
-    return is_palette_index_valid(this->transparentPixel()) ? SkEncodedInfo::kBinary_Alpha
-                                                            : SkEncodedInfo::kOpaque_Alpha;
+    return is_palette_index_valid(this->transparentPixel());
 }
 
 void SkFrameHolder::setAlphaAndRequiredFrame(SkFrame* frame) {
-    const bool reportsAlpha = frame->reportedAlpha() != SkEncodedInfo::kOpaque_Alpha;
+    const bool reportsAlpha = frame->reportsAlpha();
     const auto screenRect = SkIRect::MakeWH(fScreenWidth, fScreenHeight);
     const auto frameRect = frame_rect_on_screen(frame->frameRect(), screenRect);
 
diff --git a/third_party/gif/SkGifImageReader.h b/third_party/gif/SkGifImageReader.h
index 5d8597fccf..b5eca10dfb 100644
--- a/third_party/gif/SkGifImageReader.h
+++ b/third_party/gif/SkGifImageReader.h
@@ -247,7 +247,7 @@ public:
     SkGIFColorMap& localColorMap() { return m_localColorMap; }
 
 protected:
-    SkEncodedInfo::Alpha onReportedAlpha() const override;
+    bool onReportsAlpha() const override;
 
 private:
     int m_transparentPixel; // Index of transparent pixel. Value is kNotFound if there is no transparent pixel.