PPC: Fix trampoline pool blocking.

src/ppc/assembler-ppc.h

Index: src/ppc/assembler-ppc.h
diff --git a/src/ppc/assembler-ppc.h b/src/ppc/assembler-ppc.h
index 099aa8a1422d09943d6a059deb7d05a6d8858a26..36843c17ab9ecf61ecc1a555b0c169f997902bca 100644
--- a/src/ppc/assembler-ppc.h
+++ b/src/ppc/assembler-ppc.h
@@ -1310,7 +1310,10 @@ class Assembler : public AssemblerBase {
   }
 
   void StartBlockTrampolinePool() { trampoline_pool_blocked_nesting_++; }
-  void EndBlockTrampolinePool() { trampoline_pool_blocked_nesting_--; }
+  void EndBlockTrampolinePool() {
+    int count = --trampoline_pool_blocked_nesting_;
+    if (count == 0) CheckTrampolinePoolQuick();
+  }
   bool is_trampoline_pool_blocked() const {
     return trampoline_pool_blocked_nesting_ > 0;
   }