[Jank]: Add uri trace events

To investigate jank found in UMA sampling profiler.

Bug: chromium:1081433
Change-Id: I457731380505af5a4d7a0c30d01b4049ffd2b436
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2242037
Commit-Queue: Etienne Pierre-Doray <etiennep@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68326}

src/strings/uri.cc

@@ -10,6 +10,7 @@
 #include "src/strings/char-predicates-inl.h"
 #include "src/strings/string-search.h"
 #include "src/strings/unicode-inl.h"
+#include "src/tracing/trace-event.h"
 
 namespace v8 {
 namespace internal {
@@ -174,6 +175,8 @@ bool IntoOneAndTwoByte(Handle<String> uri, bool is_uri,
 
 MaybeHandle<String> Uri::Decode(Isolate* isolate, Handle<String> uri,
                                 bool is_uri) {
+  TRACE_EVENT0("v8", "V8.DecodeUri");
+
   uri = String::Flatten(isolate, uri);
   std::vector<uint8_t> one_byte_buffer;
   std::vector<uc16> two_byte_buffer;
@@ -278,6 +281,8 @@ void EncodePair(uc16 cc1, uc16 cc2, std::vector<uint8_t>* buffer) {
 
 MaybeHandle<String> Uri::Encode(Isolate* isolate, Handle<String> uri,
                                 bool is_uri) {
+  TRACE_EVENT0("v8", "V8.EncodeUri");
+
   uri = String::Flatten(isolate, uri);
   int uri_length = uri->length();
   std::vector<uint8_t> buffer;