[v8] Add feature flag for MinorMC

Bug: v8:12612
Change-Id: I017e22445f5429663daa692cc5bdee4e866f528e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4498627
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Omer Katz <omerkatz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1138346}

gin/gin_features.cc

@@ -87,6 +87,9 @@ BASE_FEATURE(kV8Turbofan, "V8Turbofan", base::FEATURE_ENABLED_BY_DEFAULT);
 // Enables experimental Maglev compiler.
 BASE_FEATURE(kV8Maglev, "V8Maglev", base::FEATURE_DISABLED_BY_DEFAULT);
 
+// Enables MinorMC young generation garbage collector.
+BASE_FEATURE(kV8MinorMC, "V8MinorMC", base::FEATURE_DISABLED_BY_DEFAULT);
+
 // Enables Sparkplug compiler. Note that this only sets the V8 flag when
 // manually overridden; otherwise it defers to whatever the V8 default is.
 BASE_FEATURE(kV8Sparkplug, "V8Sparkplug", base::FEATURE_ENABLED_BY_DEFAULT);

gin/gin_features.h

@@ -28,6 +28,7 @@ GIN_EXPORT BASE_DECLARE_FEATURE(kV8FlushBytecode);
 GIN_EXPORT BASE_DECLARE_FEATURE(kV8FlushEmbeddedBlobICache);
 GIN_EXPORT BASE_DECLARE_FEATURE(kV8LazyFeedbackAllocation);
 GIN_EXPORT BASE_DECLARE_FEATURE(kV8Maglev);
+GIN_EXPORT BASE_DECLARE_FEATURE(kV8MinorMC);
 GIN_EXPORT BASE_DECLARE_FEATURE(kV8MegaDomIC);
 GIN_EXPORT BASE_DECLARE_FEATURE(kV8MemoryReducerSingleGC);
 GIN_EXPORT BASE_DECLARE_FEATURE(kV8NoReclaimUnmodifiedWrappers);

gin/v8_initializer.cc

@@ -285,6 +285,7 @@ void SetFlags(IsolateHolder::ScriptMode mode,
   SetV8FlagsIfOverridden(features::kV8MegaDomIC, "--mega-dom-ic",
                          "--no-mega-dom-ic");
   SetV8FlagsIfOverridden(features::kV8Maglev, "--maglev", "--no-maglev");
+  SetV8FlagsIfOverridden(features::kV8MinorMC, "--minor-mc", "--no-minor-mc");
   SetV8FlagsIfOverridden(features::kV8Sparkplug, "--sparkplug",
                          "--no-sparkplug");
   SetV8FlagsIfOverridden(features::kV8Turbofan, "--turbofan", "--no-turbofan");