CPU profiler: limit the number of simultaneously collected profiles.

src/profile-generator.cc

Index: src/profile-generator.cc
diff --git a/src/profile-generator.cc b/src/profile-generator.cc
index 1c6c902a4dcd9c7abe5e5eddb6aac11d5b108484..2de7a2fb912ae8a444524a9ca5ce7f27ee207d65 100644
--- a/src/profile-generator.cc
+++ b/src/profile-generator.cc
@@ -492,6 +492,10 @@ CpuProfilesCollection::~CpuProfilesCollection() {
 bool CpuProfilesCollection::StartProfiling(const char* title, unsigned uid) {
   ASSERT(uid > 0);
   current_profiles_semaphore_->Wait();
+  if (current_profiles_.length() >= kMaxSimultaneousProfiles) {
+    current_profiles_semaphore_->Signal();
+    return false;
+  }
   for (int i = 0; i < current_profiles_.length(); ++i) {
     if (strcmp(current_profiles_[i]->title(), title) == 0) {
       // Ignore attempts to start profile with the same title.