Fix TextBlobTest valgrind error

tests/TextBlobTest.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkPaint.h"
 #include "SkPoint.h"
 #include "SkTextBlob.h"
 
 #include "Test.h"
 
-
 class TextBlobTester {
 public:
     // This unit test feeds an SkTextBlobBuilder various runs then checks to see if
     // the result contains the provided data and merges runs when appropriate.
     static void TestBuilder(skiatest::Reporter* reporter) {
         SkTextBlobBuilder builder;
 
         // empty run set
         RunBuilderTest(reporter, builder, nullptr, 0, nullptr, 0);
 
@@ skipping 123 matching lines @@
             REPORTER_ASSERT(reporter, blob->bounds().isEmpty());
         }
 
         // Implicit bounds
 
         {
             // Exercise the empty bounds path, and ensure that RunRecord-aligned pos buffers
             // don't trigger asserts (http://crbug.com/542643).
             SkPaint p;
             p.setTextSize(0);
-            p.setTextEncoding(SkPaint::kGlyphID_TextEncoding);
+            p.setTextEncoding(SkPaint::kUTF8_TextEncoding);
 
             const char* txt = "BOOO";
-            const size_t len = strlen(txt);
-            const SkTextBlobBuilder::RunBuffer& buffer = builder.allocRunPos(p, (int)len);
-            p.textToGlyphs(txt, len, buffer.glyphs);
-            memset(buffer.pos, 0, sizeof(SkScalar) * len * 2);
+            const size_t txtLen = strlen(txt);
+            const int glyphCount = p.textToGlyphs(txt, txtLen, nullptr);
+
+            p.setTextEncoding(SkPaint::kGlyphID_TextEncoding);
+            const SkTextBlobBuilder::RunBuffer& buffer = builder.allocRunPos(p, glyphCount);
+
+            p.setTextEncoding(SkPaint::kUTF8_TextEncoding);
+            p.textToGlyphs(txt, txtLen, buffer.glyphs);
+
+            memset(buffer.pos, 0, sizeof(SkScalar) * glyphCount * 2);
             SkAutoTUnref<const SkTextBlob> blob(builder.build());
             REPORTER_ASSERT(reporter, blob->bounds().isEmpty());
         }
     }
 
 private:
     struct RunDef {
         unsigned                     count;
         SkTextBlob::GlyphPositioning pos;
         SkScalar                     x, y;
@@ skipping 74 matching lines @@
         default:
             SkFAIL("unhandled positioning value");
         }
     }
 };
 
 DEF_TEST(TextBlob_builder, reporter) {
     TextBlobTester::TestBuilder(reporter);
     TextBlobTester::TestBounds(reporter);
 }