Fix trace_event code to accept double-quote and backslash characters in string values

BUG=95602
TEST=base_unittests

Review URL: http://codereview.chromium.org/7840017

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@99882 0039d316-1c4b-4281-b951-d872f2087c98

base/debug/trace_event.cc

@@ -87,10 +87,13 @@ void TraceValue::AppendAsJSON(std::string* out) const {
       *out += "\"";
       start_pos = out->size();
       *out += as_string() ? as_string() : "NULL";
-      // replace " character with '
-      while ((start_pos = out->find_first_of('\"', start_pos)) !=
-             std::string::npos)
-        (*out)[start_pos] = '\'';
+      // insert backslash before special characters for proper json format.
+      while ((start_pos = out->find_first_of("\\\"", start_pos)) !=
+             std::string::npos) {
+        out->insert(start_pos, 1, '\\');
+        // skip inserted escape character and following character.
+        start_pos += 2;
+      }
       *out += "\"";
       break;
     default:

base/debug/trace_event_unittest.cc

@@ -206,8 +206,8 @@ void TraceWithAllMacroVariants(WaitableEvent* task_complete_event) {
     TRACE_EVENT0("all", "TRACE_EVENT0 call");
     TRACE_EVENT1("all", "TRACE_EVENT1 call", "name1", "value1");
     TRACE_EVENT2("all", "TRACE_EVENT2 call",
-                 "name1", "value1",
-                 "name2", "value2");
+                 "name1", "\"value1\"",
+                 "name2", "value\\2");
 
     TRACE_EVENT_INSTANT0("all", "TRACE_EVENT_INSTANT0 call");
     TRACE_EVENT_INSTANT1("all", "TRACE_EVENT_INSTANT1 call", "name1", "value1");
@@ -269,9 +269,9 @@ void ValidateAllTraceMacrosCreatedData(const ListValue& trace_parsed,
   EXPECT_FIND_("TRACE_EVENT1 call");
   EXPECT_FIND_("TRACE_EVENT2 call");
   EXPECT_SUB_FIND_("name1");
-  EXPECT_SUB_FIND_("value1");
+  EXPECT_SUB_FIND_("\"value1\"");
   EXPECT_SUB_FIND_("name2");
-  EXPECT_SUB_FIND_("value2");
+  EXPECT_SUB_FIND_("value\\2");
   EXPECT_FIND_("TRACE_EVENT_INSTANT0 call");
   EXPECT_FIND_("TRACE_EVENT_INSTANT1 call");
   EXPECT_FIND_("TRACE_EVENT_INSTANT2 call");