added some missing static modifiers
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1690683002

Review URL: https://codereview.chromium.org/1690683002
diff --git a/tools/debugger/SkDrawCommand.cpp b/tools/debugger/SkDrawCommand.cpp
index e9cdd32..bca5186 100644
--- a/tools/debugger/SkDrawCommand.cpp
+++ b/tools/debugger/SkDrawCommand.cpp
@@ -567,13 +567,14 @@
     };
 }
 
-void store_scalar(Json::Value* target, const char* key, SkScalar value, SkScalar defaultValue) {
+static void store_scalar(Json::Value* target, const char* key, SkScalar value, 
+                         SkScalar defaultValue) {
     if (value != defaultValue) {
         (*target)[key] = Json::Value(value);
     }
 }
 
-void store_bool(Json::Value* target, const char* key, bool value, bool defaultValue) {
+static void store_bool(Json::Value* target, const char* key, bool value, bool defaultValue) {
     if (value != defaultValue) {
         (*target)[key] = Json::Value(value);
     }