[DevTools] Roll inspector_protocol (Chromium)

"Tweaks for emitting JSON"
https://chromium-review.googlesource.com/c/deps/inspector_protocol/+/2071518

TBR=caseq

Change-Id: I6dc2c9270805b8dca1bca453939459bfcbff2a9f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2072854Reviewed-by: Johannes Henkel <johannes@chromium.org>
Commit-Queue: Johannes Henkel <johannes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#745236}

third_party/inspector_protocol/README.chromium

@@ -2,7 +2,7 @@ Name: inspector protocol
 Short Name: inspector_protocol
 URL: https://chromium.googlesource.com/deps/inspector_protocol/
 Version: 0
-Revision: 1f2492b6768e8620ece36a784c8ecd7ae7091610
+Revision: 81ef742ba3587767fc08652d299df9e9b7051407
 License: BSD
 License File: LICENSE
 Security Critical: yes

third_party/inspector_protocol/crdtp/json.cc

@@ -285,7 +285,22 @@ class JSONEncoder : public ParserHandler {
       Emit("null");
       return;
     }
+    // If |value| is a scalar, emit it as an int. Taken from json_writer.cc in
+    // Chromium.
+    if (value <= std::numeric_limits<int64_t>::max() &&
+        value >= std::numeric_limits<int64_t>::min() &&
+        std::floor(value) == value) {
+      Emit(std::to_string(static_cast<int64_t>(value)));
+      return;
+    }
     std::string str_value = json::platform::DToStr(value);
+    // The following is somewhat paranoid, but also taken from json_writer.cc
+    // in Chromium:
+    // Ensure that the number has a .0 if there's no decimal or 'e'.  This
+    // makes sure that when we read the JSON back, it's interpreted as a
+    // real rather than an int.
+    if (str_value.find_first_of(".eE") == std::string::npos)
+      str_value.append(".0");
 
     // DToStr may fail to emit a 0 before the decimal dot. E.g. this is
     // the case in base::NumberToString in Chromium (which is based on

third_party/inspector_protocol/crdtp/json_test.cc

@@ -184,6 +184,32 @@ TEST(JsonStdStringWriterTest, HelloWorld) {
       out);
 }
 
+TEST(JsonStdStringWriterTest, ScalarsAreRenderedAsInt) {
+  // Test that Number.MIN_SAFE_INTEGER / Number.MAX_SAFE_INTEGER from Javascript
+  // are rendered as integers (no decimal point / rounding), even when we
+  // encode them from double. Javascript's Number is an IEE754 double, so
+  // it has 53 bits to represent integers.
+  std::string out;
+  Status status;
+  std::unique_ptr<ParserHandler> writer = NewJSONEncoder(&out, &status);
+  writer->HandleMapBegin();
+
+  writer->HandleString8(SpanFrom("Number.MIN_SAFE_INTEGER"));
+  EXPECT_EQ(-0x1fffffffffffff, -9007199254740991);  // 53 bits for integers.
+  writer->HandleDouble(-9007199254740991);          // Note HandleDouble here.
+
+  writer->HandleString8(SpanFrom("Number.MAX_SAFE_INTEGER"));
+  EXPECT_EQ(0x1fffffffffffff, 9007199254740991);  // 53 bits for integers.
+  writer->HandleDouble(9007199254740991);         // Note HandleDouble here.
+
+  writer->HandleMapEnd();
+  EXPECT_TRUE(status.ok());
+  EXPECT_EQ(
+      "{\"Number.MIN_SAFE_INTEGER\":-9007199254740991,"
+      "\"Number.MAX_SAFE_INTEGER\":9007199254740991}",
+      out);
+}
+
 TEST(JsonStdStringWriterTest, RepresentingNonFiniteValuesAsNull) {
   // JSON can't represent +Infinity, -Infinity, or NaN.
   // So in practice it's mapped to null.