Move font loading in gm tests and benches out of constructors

gm/textblob.cpp

Index: gm/textblob.cpp
diff --git a/gm/textblob.cpp b/gm/textblob.cpp
index 7c0fd875462cba46574636a53e7a94355649f159..e85571f898f8a2a9038f69fa5256c6c56b47aa82 100644
--- a/gm/textblob.cpp
+++ b/gm/textblob.cpp
@@ -67,17 +67,21 @@ const SkScalar kFontSize = 16;
 class TextBlobGM : public skiagm::GM {
 public:
     TextBlobGM(const char* txt)
-        : fTypeface(sk_tool_utils::create_portable_typeface("Times", SkTypeface::kNormal)) {
+        : fText(txt) {
+    }
+
+protected:
+    void onOnceBeforeDraw() override {
+        fTypeface.reset(sk_tool_utils::create_portable_typeface("Times", SkTypeface::kNormal));
         SkPaint p;
         p.setTypeface(fTypeface);
-        size_t txtLen = strlen(txt);
-        int glyphCount = p.textToGlyphs(txt, txtLen, NULL);
+        size_t txtLen = strlen(fText);
+        int glyphCount = p.textToGlyphs(fText, txtLen, NULL);
 
         fGlyphs.append(glyphCount);
-        p.textToGlyphs(txt, txtLen, fGlyphs.begin());
+        p.textToGlyphs(fText, txtLen, fGlyphs.begin());
     }
 
-protected:
     SkString onShortName() override {
         return SkString("textblob");
     }
@@ -178,7 +182,7 @@ private:
 
     SkTDArray<uint16_t>      fGlyphs;
     SkAutoTUnref<SkTypeface> fTypeface;
-
+    const char*              fText;
     typedef skiagm::GM INHERITED;
 };