Reland "[svg] Absolute positioning support for text"

This reverts commit e2f62453523e8eeb98968570b48b229f1cc1e712.

Reason for revert: relanding with fixes

Original change's description:
> Revert "[svg] Absolute positioning support for text"
>
> This reverts commit febb1b87a5e73bdbe2cb598783082d3644d0e969.
>
> Reason for revert: breaking the android roll
>
> Original change's description:
> > [svg] Absolute positioning support for text
> >
> > Implement per-character position attribute lookup based on [1]:
> >
> >   - convert "x" and "y" attributes to arrays
> >   - introduce ScopedPosResolver to handle positioning attribute lookup
> >     and fallback
> >   - push a new resolver every time we enter a text positioning element
> >     scope (<text>, <tspan>, etc).
> >   - flush/reposition a new text chunk every time we encounter explicit
> >     absolute positions
> >
> > The position attribute fallback logic is complex enough to warrant a
> > unit test.
> >
> > [1] https://www.w3.org/TR/SVG11/text.html#TSpanElementXAttribute
> >
> > Bug: skia:10840
> > Change-Id: I66c478fea4a179fdb8b1a6a9ff00c4dd9509f8d2
> > Reviewed-on: https://skia-review.googlesource.com/c/skia/+/345161
> > Commit-Queue: Florin Malita <fmalita@chromium.org>
> > Commit-Queue: Florin Malita <fmalita@google.com>
> > Reviewed-by: Tyler Denniston <tdenniston@google.com>
>
> TBR=fmalita@chromium.org,fmalita@google.com,tdenniston@google.com
>
> Change-Id: I80e3396d555369fe835ee73102135061f63e8bf0
> No-Presubmit: true
> No-Tree-Checks: true
> No-Try: true
> Bug: skia:10840
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/345417
> Reviewed-by: Derek Sollenberger <djsollen@google.com>
> Commit-Queue: Derek Sollenberger <djsollen@google.com>

TBR=djsollen@google.com,fmalita@chromium.org,fmalita@google.com,tdenniston@google.com

# Not skipping CQ checks because this is a reland.

Bug: skia:10840
Change-Id: I4c6f6a9f19c0f7598bdcf34e915f43c139b995a9
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/345420
Reviewed-by: Florin Malita <fmalita@google.com>
Commit-Queue: Florin Malita <fmalita@google.com>
diff --git a/BUILD.gn b/BUILD.gn
index a0ea1f2..6603535 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -1900,7 +1900,7 @@
       "modules/skparagraph:tests",
       "modules/sksg:tests",
       "modules/skshaper",
-      "modules/svg",
+      "modules/svg:tests",
       "//third_party/libpng",
       "//third_party/libwebp",
       "//third_party/zlib",