diff --git a/include/core/SkFont.h b/include/core/SkFont.h
index 08928ae4ec..ce910bb739 100644
--- a/include/core/SkFont.h
+++ b/include/core/SkFont.h
@@ -495,6 +495,7 @@ private:
     void glyphsToUnichars(const SkGlyphID glyphs[], int count, SkUnichar text[]) const;
 
     friend class SkCanonicalizeFont;
+    friend class SkFontPriv;
     friend class SkPaint;
     friend class SVGTextBuilder;
 };
diff --git a/src/core/SkFont.cpp b/src/core/SkFont.cpp
index db07281c57..6db43ea0b5 100644
--- a/src/core/SkFont.cpp
+++ b/src/core/SkFont.cpp
@@ -186,7 +186,7 @@ void SkFont::glyphsToUnichars(const SkGlyphID glyphs[], int count, SkUnichar tex
 
     auto typeface = SkFontPriv::GetTypefaceOrDefault(*this);
     const unsigned numGlyphsInTypeface = typeface->countGlyphs();
-    SkAutoTArray<SkUnichar> unichars(count);
+    SkAutoTArray<SkUnichar> unichars(numGlyphsInTypeface);
     typeface->getGlyphToUnicodeMap(unichars.get());
 
     for (int i = 0; i < count; ++i) {
@@ -558,3 +558,7 @@ int SkFontPriv::CountTextElements(const void* text, size_t byteLength, SkTextEnc
     return 0;
 }
 
+void SkFontPriv::GlyphsToUnichars(const SkFont& font, const uint16_t glyphs[], int count,
+                                  SkUnichar uni[]) {
+    font.glyphsToUnichars(glyphs, count, uni);
+}
diff --git a/src/core/SkFontPriv.h b/src/core/SkFontPriv.h
index a0bbec3ae4..6b34aa0214 100644
--- a/src/core/SkFontPriv.h
+++ b/src/core/SkFontPriv.h
@@ -61,6 +61,8 @@ public:
 
     // Returns the number of elements (characters or glyphs) in the array.
     static int CountTextElements(const void* text, size_t byteLength, SkTextEncoding);
+
+    static void GlyphsToUnichars(const SkFont&, const uint16_t glyphs[], int count, SkUnichar[]);
 };
 
 class SkAutoToGlyphs {
diff --git a/tests/UnicodeTest.cpp b/tests/UnicodeTest.cpp
index 62174e9809..fac3eb9cc2 100644
--- a/tests/UnicodeTest.cpp
+++ b/tests/UnicodeTest.cpp
@@ -47,3 +47,24 @@ DEF_TEST(Unicode_textencodings, reporter) {
     REPORTER_ASSERT(reporter, !memcmp(glyphs8, glyphs16, count8 * sizeof(uint16_t)));
     REPORTER_ASSERT(reporter, !memcmp(glyphs8, glyphs32, count8 * sizeof(uint16_t)));
 }
+
+#include "SkFont.h"
+#include "SkFontPriv.h"
+
+DEF_TEST(glyphs_to_unichars, reporter) {
+    SkFont font;
+
+    const int N = 52;
+    SkUnichar uni[N];
+    for (int i = 0; i < 26; ++i) {
+        uni[i +  0] = i + 'A';
+        uni[i + 26] = i + 'a';
+    }
+    uint16_t glyphs[N];
+    font.textToGlyphs(uni, sizeof(uni), kUTF32_SkTextEncoding, glyphs, N);
+
+    SkUnichar uni2[N];
+    SkFontPriv::GlyphsToUnichars(font, glyphs, N, uni2);
+    REPORTER_ASSERT(reporter, memcmp(uni, uni2, sizeof(uni)) == 0);
+}
+