Analytics: add simple framework for game quirks reporting

And use it for reporting games that rely on ICache emulation to some
degree. We know of a few but it would be interesting to get a more
exhaustive list from crowdsourcing.

Source/Core/Core/Analytics.cpp

@@ -131,9 +131,34 @@ void DolphinAnalytics::ReportGameStart()
   builder.AddData("type", "game-start");
   Send(builder);
 
+  // Reset per-game state.
+  m_reported_quirks.fill(false);
   InitializePerformanceSampling();
 }
 
+// Keep in sync with enum class GameQuirk definition.
+const char* GAME_QUIRKS_NAMES[] = {
+    "icache-matters",  // ICACHE_MATTERS
+};
+static_assert(sizeof(GAME_QUIRKS_NAMES) / sizeof(GAME_QUIRKS_NAMES[0]) ==
+                  static_cast<u32>(GameQuirk::COUNT),
+              "Game quirks names and enum definition are out of sync.");
+
+void DolphinAnalytics::ReportGameQuirk(GameQuirk quirk)
+{
+  u32 quirk_idx = static_cast<u32>(quirk);
+
+  // Only report once per run.
+  if (m_reported_quirks[quirk_idx])
+    return;
+  m_reported_quirks[quirk_idx] = true;
+
+  Common::AnalyticsReportBuilder builder(m_per_game_builder);
+  builder.AddData("type", "quirk");
+  builder.AddData("quirk", GAME_QUIRKS_NAMES[quirk_idx]);
+  Send(builder);
+}
+
 void DolphinAnalytics::ReportPerformanceInfo(PerformanceSample&& sample)
 {
   if (ShouldStartPerformanceSampling())