Properly suspend HTMLDocumentParser

Source/core/html/parser/HTMLParserScheduler.h

Index: Source/core/html/parser/HTMLParserScheduler.h
diff --git a/Source/core/html/parser/HTMLParserScheduler.h b/Source/core/html/parser/HTMLParserScheduler.h
index 5c853a30d111ddc096f2b9a5a582181ce94945e5..a69a67b6e7a34d0de3227a21f676e1281c7c7719 100644
--- a/Source/core/html/parser/HTMLParserScheduler.h
+++ b/Source/core/html/parser/HTMLParserScheduler.h
@@ -77,6 +77,15 @@ public:
 
     bool yieldIfNeeded(const SpeculationsPumpSession&);
 
+    /**
+     * Can only be called if this scheduler is suspended. If this is called,
+     * then after the scheduler is resumed by calling resume(), this call
+     * ensures that HTMLDocumentParser::resumeAfterYield will be called. Used to
+     * signal this scheduler that the background html parser sent chunks to
+     * HTMLDocumentParser while it was suspended.
+     */
+    void forceResumeAfterYield();
+
     void suspend();
     void resume();