Reland "Removing ICU dependencies from skparagraph BUILD.gn file"

This reverts commit 05ce2817f2a060caf8acd5be25b4f29875d63049.

Reason for revert: Fixing the build

Original change's description:
> Revert "Removing ICU dependencies from skparagraph BUILD.gn file"
>
> This reverts commit f1711adb1a04595eba1e9984976bfb92d41d0035.
>
> Reason for revert: Build break
>
> Original change's description:
> > Removing ICU dependencies from skparagraph BUILD.gn file
> >
> > (and from the sources, too)
> >
> > Change-Id: I9d8ff51c91aad4b770b1f183c04734d31252b851
> > Reviewed-on: https://skia-review.googlesource.com/c/skia/+/313148
> > Commit-Queue: Julia Lavrova <jlavrova@google.com>
> > Reviewed-by: Ben Wagner <bungeman@google.com>
>
> TBR=bungeman@google.com,jlavrova@google.com
>
> Change-Id: I1fce2436855e3e2a4cb7d1d7204b3ae49fd530e8
> No-Presubmit: true
> No-Tree-Checks: true
> No-Try: true
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/314540
> Reviewed-by: Julia Lavrova <jlavrova@google.com>
> Commit-Queue: Julia Lavrova <jlavrova@google.com>

TBR=bungeman@google.com,jlavrova@google.com

Change-Id: I13d78d75698df47930adc2514d1328abc556a209
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/316444
Reviewed-by: Kevin Lubick <kjlubick@google.com>
Commit-Queue: Julia Lavrova <jlavrova@google.com>
diff --git a/modules/skshaper/src/SkUnicode.h b/modules/skshaper/src/SkUnicode.h
index 3bbb02e..5414ed2 100644
--- a/modules/skshaper/src/SkUnicode.h
+++ b/modules/skshaper/src/SkUnicode.h
@@ -9,6 +9,7 @@
 
 #include "include/core/SkTypes.h"
 #include "src/core/SkSpan.h"
+#include "src/utils/SkUTF.h"
 #include <vector>
 
 #if !defined(SKUNICODE_IMPLEMENTATION)
@@ -89,6 +90,10 @@
 
         virtual ~SkUnicode() = default;
 
+        virtual bool isControl(SkUnichar utf8) = 0;
+        virtual bool isWhitespace(SkUnichar utf8) = 0;
+        virtual SkString convertUtf16ToUtf8(const std::u16string& utf16) = 0;
+
         // Iterators (used in SkShaper)
         virtual std::unique_ptr<SkBidiIterator> makeBidiIterator
             (const uint16_t text[], int count, SkBidiIterator::Direction) = 0;