[Local GC] Remove static fields from GC interface (#10566)

* Remove max_generation from GC interface

* [Local GC] Clean up the GC interface by removing all static fields
from it:
  1) gcHeapType is replaced by g_heap_type (EE side) and g_gc_heap_type
     (GC side), each of which is set on initialization. g_heap_type is
     read by the DAC to determine what kind of heap is being used.
  2) maxGeneration is not necessary due to the GC DAC changes.

* Rebase against master

* Comments and cleanup

* Use a heap allocation instead of alloca

* Code review feedback: remove a redundant cast and allocate generation count table once, on first use

* Address code review feedback: cache some calls to GetMaxGeneration

1 files changed, 1 insertions, 0 deletions

diff --git a/src/vm/threads.h b/src/vm/threads.h
index f34066feb3..697ffea454 100644
--- a/src/vm/threads.h
+++ b/src/vm/threads.h
@@ -5555,6 +5555,7 @@ private:
 private:
     static LONG s_DeadThreadCountThresholdForGCTrigger;
     static DWORD s_DeadThreadGCTriggerPeriodMilliseconds;
+    static SIZE_T *s_DeadThreadGenerationCounts;
 
 public: