Revert "Reland "Reland "Add new method for storing DrawOpAtlas texture index."""

This reverts commit 3b9c544bf86f930a29231ad997cb6cfad9055f66.

Reason for revert: Probably causing text issues in Chrome

Original change's description:
> Reland "Reland "Add new method for storing DrawOpAtlas texture index.""
> 
> This is a reland of dea2f34f09c3d0326b36099b406fa546f2b8fd96
> 
> Original change's description:
> > Reland "Add new method for storing DrawOpAtlas texture index."
> > 
> > This is a reland of c8b2e615400fe43b74dbbd2d7167bb97bd032f87
> > 
> > Original change's description:
> > > Add new method for storing DrawOpAtlas texture index.
> > > 
> > > Storing the texture index in the lower bit of each texture coordinate
> > > seems to have issues on certain iOS devices. Rather than do that, we
> > > use the sign of the texture coordinate to act as our storage bit.
> > > To manage encoding 0 we map [0, N] to [-1, -N-1] to represent a bit.
> > > 
> > > Change-Id: Ic588ee92cf858915a1833cf482d4b23bd11c1000
> > > Reviewed-on: https://skia-review.googlesource.com/c/skia/+/263561
> > > Commit-Queue: Jim Van Verth <jvanverth@google.com>
> > > Reviewed-by: Brian Osman <brianosman@google.com>
> > 
> > Change-Id: I901502c3d83ff9727c51ad4447b0cee733257649
> > Reviewed-on: https://skia-review.googlesource.com/c/skia/+/264566
> > Reviewed-by: Jim Van Verth <jvanverth@google.com>
> > Commit-Queue: Jim Van Verth <jvanverth@google.com>
> 
> Change-Id: I000bb74ca57e321084ca2d1d9dc2f0274880c0da
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/264689
> Reviewed-by: Jim Van Verth <jvanverth@google.com>
> Commit-Queue: Jim Van Verth <jvanverth@google.com>

TBR=jvanverth@google.com,brianosman@google.com
Bug: 1045016

# Not skipping CQ checks because original CL landed > 1 day ago.

Change-Id: Ie376c7b3cb359f5378e4dd983a103da81ec92e5d
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/266557
Reviewed-by: Jim Van Verth <jvanverth@google.com>
Commit-Queue: Jim Van Verth <jvanverth@google.com>
diff --git a/src/gpu/ops/GrAtlasTextOp.cpp b/src/gpu/ops/GrAtlasTextOp.cpp
index 24495d2..f790870 100644
--- a/src/gpu/ops/GrAtlasTextOp.cpp
+++ b/src/gpu/ops/GrAtlasTextOp.cpp
@@ -192,22 +192,17 @@
             // In the LCD case the color will be garbage, but we'll overwrite it with the texcoords
             // and it avoids a lot of conditionals.
             auto color = *reinterpret_cast<const SkColor*>(blobVertices + sizeof(SkPoint));
-            size_t coordOffset = vertexStride - 2*sizeof(int16_t);
-            auto* blobCoordsLT = reinterpret_cast<const int16_t*>(blobVertices + coordOffset);
-            auto* blobCoordsRB = reinterpret_cast<const int16_t*>(blobVertices + 3 * vertexStride +
+            size_t coordOffset = vertexStride - 2*sizeof(uint16_t);
+            auto* blobCoordsLT = reinterpret_cast<const uint16_t*>(blobVertices + coordOffset);
+            auto* blobCoordsRB = reinterpret_cast<const uint16_t*>(blobVertices + 3 * vertexStride +
                                                                    coordOffset);
             // Pull out the texel coordinates and texture index bits
-            int16_t coordsRectL = blobCoordsLT[0];
-            int16_t coordsRectT = blobCoordsLT[1];
-            int16_t coordsRectR = blobCoordsRB[0];
-            int16_t coordsRectB = blobCoordsRB[1];
-            int index0, index1;
-
-            std::tie(coordsRectL, coordsRectT, index0) =
-                    GrDrawOpAtlas::UnpackIndexFromTexCoords(coordsRectL, coordsRectT);
-            std::tie(coordsRectR, coordsRectB, index1) =
-                    GrDrawOpAtlas::UnpackIndexFromTexCoords(coordsRectR, coordsRectB);
-            SkASSERT(index0 == index1);
+            uint16_t coordsRectL = blobCoordsLT[0] >> 1;
+            uint16_t coordsRectT = blobCoordsLT[1] >> 1;
+            uint16_t coordsRectR = blobCoordsRB[0] >> 1;
+            uint16_t coordsRectB = blobCoordsRB[1] >> 1;
+            uint16_t pageIndexX = blobCoordsLT[0] & 0x1;
+            uint16_t pageIndexY = blobCoordsLT[1] & 0x1;
 
             int positionRectWidth = positionRect.width();
             int positionRectHeight = positionRect.height();
@@ -233,10 +228,10 @@
             positionRect.fBottom -= delta;
 
             // Repack texel coordinates and index
-            std::tie(coordsRectL, coordsRectT) =
-                    GrDrawOpAtlas::PackIndexInTexCoords(coordsRectL, coordsRectT, index0);
-            std::tie(coordsRectR, coordsRectB) =
-                    GrDrawOpAtlas::PackIndexInTexCoords(coordsRectR, coordsRectB, index1);
+            coordsRectL = coordsRectL << 1 | pageIndexX;
+            coordsRectT = coordsRectT << 1 | pageIndexY;
+            coordsRectR = coordsRectR << 1 | pageIndexX;
+            coordsRectB = coordsRectB << 1 | pageIndexY;
 
             // Set new positions and coords
             SkPoint* currPosition = reinterpret_cast<SkPoint*>(currVertex);