Revert of Add gamma/sRGB tags to SkImageInfo (patchset #1 of https://codereview.chromium.org/517123002/)

Reason for revert:
Seems to be triggering assert in blink

SSLUITest.TestRedirectHTTPToBadHTTPS (run #1):
[ RUN      ] SSLUITest.TestRedirectHTTPToBadHTTPS
HTTP server started on http://127.0.0.1:58000...
sending server_data: {"host": "127.0.0.1", "port": 58000} (36 bytes)
HTTPS server started on https://127.0.0.1:58009...
sending server_data: {"host": "127.0.0.1", "port": 58009} (36 bytes)
ASSERTION FAILED: info.fAlphaType == m_imageInfo.fAlphaType
../../third_party/WebKit/Source/platform/graphics/DecodingImageGenerator.cpp(78) : virtual bool blink::DecodingImageGenerator::onGetPixels(const SkImageInfo &, void *, size_t, SkPMColor *, int *)
1   0x77eb0d3 blink::DecodingImageGenerator::onGetPixels(SkImageInfo const&, void*, unsigned long, unsigned int*, int*)
2   0x92edddc SkImageGenerator::getPixels(SkImageInfo const&, void*, unsigned long, unsigned int*, int*)
3   0x92adf78 SkDiscardablePixelRef::onNewLockPixels(SkPixelRef::LockRec*)
4   0x9369283 SkPixelRef::lockPixels(SkPixelRef::LockRec*)
5   0x9369433 SkPixelRef::lockPixels()
6   0x9213344 SkBitmap::lockPixels() const
7   0x921ca57 SkAutoLockPixels::SkAutoLockPixels(SkBitmap const&, bool)
8   0x921ad80 SkAutoLockPixels::SkAutoLockPixels(SkBitmap const&, bool)
9   0x92b7125 SkDraw::drawBitmap(SkBitmap const&, SkMatrix const&, SkPaint const&) const
10  0x921f4fb SkBitmapDevice::drawBitmap(SkDraw const&, SkBitmap const&, SkMatrix const&, SkPaint const&)
11  0x921f8c7 SkBitmapDevice::drawBitmapRect(SkDraw const&, SkBitmap const&, SkRect const*, SkRect const&, SkPaint const&, SkCanvas::DrawBitmapRectFlags)
12  0x9288e12 SkCanvas::internalDrawBitmapRect(SkBitmap const&, SkRect const*, SkRect const&, SkPaint const*, SkCanvas::DrawBitmapRectFlags)
13  0x9288ee9 SkCanvas::drawBitmapRectToRect(SkBitmap const&, SkRect const*, SkRect const&, SkPaint const*, SkCanvas::DrawBitmapRectFlags)

Original issue's description:
> Add gamma/sRGB tags to SkImageInfo
>
> requires this CL to land in chrome
> https://codereview.chromium.org/517803002/
>
> BUG=skia:
>
> Committed: https://skia.googlesource.com/skia/+/228b285ba14a6e9b6d1cc95ea1583caab30168a1

R=fmalita@google.com, fmalita@chromium.org, reed@chromium.org
TBR=fmalita@chromium.org, fmalita@google.com, reed@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Author: reed@google.com

Review URL: https://codereview.chromium.org/519583004
4 files changed