SkPDF: SkShaper_primitive uses new textblob API

BUILD.gn

Index: BUILD.gn
diff --git a/BUILD.gn b/BUILD.gn
index f1439c7857253515868d76665385449977c9f35f..e770c5bfaa773566d84162019b52e7f4839cb6e7 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -786,7 +786,7 @@ if (skia_enable_tools) {
   }
 
   if (current_cpu != "mipsel") {  # Clang 3.8 crashes while compiling hb-icu.cc for mipsel.
-    executable("sktexttopdf") {
+    executable("sktexttopdf-hb") {
       sources = [
         "tools/SkShaper_harfbuzz.cpp",
         "tools/using_skia_and_harfbuzz.cpp",
@@ -798,4 +798,14 @@ if (skia_enable_tools) {
       testonly = true
     }
   }
+  executable("sktexttopdf") {
+    sources = [
+      "tools/SkShaper_primitive.cpp",
+      "tools/using_skia_and_harfbuzz.cpp",
+    ]
+    deps = [
+      ":skia",
+    ]
+    testonly = true
+  }
 }