Unit tests for HarfBuzzShaper

Source/platform/fonts/shaping/HarfBuzzShaper.h

Index: Source/platform/fonts/shaping/HarfBuzzShaper.h
diff --git a/Source/platform/fonts/shaping/HarfBuzzShaper.h b/Source/platform/fonts/shaping/HarfBuzzShaper.h
index 405c5951d082dfcbacc90a342a390a7c7fac9f7a..1ded6875b93e8714dc49b962d10aab0593579a3c 100644
--- a/Source/platform/fonts/shaping/HarfBuzzShaper.h
+++ b/Source/platform/fonts/shaping/HarfBuzzShaper.h
@@ -50,7 +50,7 @@ class Font;
 class GlyphBuffer;
 class SimpleFontData;
 
-class HarfBuzzShaper final : public Shaper {
+class PLATFORM_EXPORT HarfBuzzShaper final : public Shaper {
 public:
     HarfBuzzShaper(const Font*, const TextRun&, const GlyphData* emphasisData = nullptr,
         HashSet<const SimpleFontData*>* fallbackFonts = nullptr, FloatRect* = nullptr);
@@ -61,6 +61,23 @@ public:
     int offsetForPosition(float targetX);
     FloatRect selectionRect(const FloatPoint&, int height, int from, int to);
 
+    unsigned numberOfRunsForTesting() const
+    {
+        return m_harfBuzzRuns.size();
+    }
+
+    bool runInfoForTesting(unsigned runIndex, unsigned& startIndex,
+        unsigned& numGlyphs, hb_script_t& script)
+    {
+        if (runIndex < m_harfBuzzRuns.size()) {
+            startIndex = m_harfBuzzRuns[runIndex]->startIndex();
+            numGlyphs = m_harfBuzzRuns[runIndex]->numGlyphs();
+            script = m_harfBuzzRuns[runIndex]->script();
+            return true;
+        }
+        return false;
+    }
+
 private:
     class HarfBuzzRun {
     public: