diff --git a/experimental/PdfViewer/SkPdfUtils.h b/experimental/PdfViewer/SkPdfUtils.h
index b18c727..08d9812 100644
--- a/experimental/PdfViewer/SkPdfUtils.h
+++ b/experimental/PdfViewer/SkPdfUtils.h
@@ -32,6 +32,7 @@
 
 struct NotOwnedString {
     const unsigned char* fBuffer;
+    // TODO(edisonn): clean up, the last two bytes are used to signal if compression is used
     size_t fBytes;
 
     static void init(NotOwnedString* str) {
@@ -50,6 +51,8 @@
     }
 };
 
+SkMatrix SkMatrixFromPdfMatrix(double array[6]);
+
 // TODO(edisonn): hack to make code generation simpler. Alternatively we can update the
 // generate_code.py not to rely on != operator
 bool operator !=(const SkString& first, const char* second);
@@ -70,4 +73,46 @@
 #define SkTraceRect(a,b)
 #endif
 
+#ifdef PDF_TRACE_TOKENIZER
+
+static void TRACE_COMMENT(char ch) {
+    printf("%c", ch);
+}
+
+static void TRACE_TK(char ch) {
+    printf("%c", ch);
+}
+
+static void TRACE_NAME(const unsigned char* start, const unsigned char* end) {
+    while (start < end) {
+        printf("%c", *start);
+        start++;
+    }
+    printf("\n");
+}
+
+static void TRACE_STRING(const unsigned char* start, const unsigned char* end) {
+    while (start < end) {
+        printf("%c", *start);
+        start++;
+    }
+    printf("\n");
+}
+
+static void TRACE_HEXSTRING(const unsigned char* start, const unsigned char* end) {
+    while (start < end) {
+        printf("%c", *start);
+        start++;
+    }
+    printf("\n");
+}
+
+#else
+#define TRACE_COMMENT(ch)
+#define TRACE_TK(ch)
+#define TRACE_NAME(start,end)
+#define TRACE_STRING(start,end)
+#define TRACE_HEXSTRING(start,end)
+#endif
+
 #endif   // SkPdfUtils_DEFINED