Bug 1804295 - Remove the current use of favorPerformanceHint, r=emilio

Differential Revision: https://phabricator.services.mozilla.com/D163964

docshell/base/nsDocShell.cpp

@@ -96,7 +96,6 @@
 #include "mozilla/net/UrlClassifierFeatureFactory.h"
 #include "ReferrerInfo.h"
 
-#include "nsIAppShell.h"
 #include "nsIAuthPrompt.h"
 #include "nsIAuthPrompt2.h"
 #include "nsICachingChannel.h"
@@ -265,17 +264,6 @@ using mozilla::ipc::Endpoint;
 // Threshold value in ms for META refresh based redirects
 #define REFRESH_REDIRECT_TIMER 15000
 
-// Hint for native dispatch of events on how long to delay after
-// all documents have loaded in milliseconds before favoring normal
-// native event dispatch priorites over performance
-// Can be overridden with docshell.event_starvation_delay_hint pref.
-#define NS_EVENT_STARVATION_DELAY_HINT 2000
-
-static NS_DEFINE_CID(kAppShellCID, NS_APPSHELL_CID);
-
-// Number of documents currently loading
-static int32_t gNumberOfDocumentsLoading = 0;
-
 static mozilla::LazyLogModule gCharsetMenuLog("CharsetMenu");
 
 #define LOGCHARSETMENU(args) \
@@ -297,16 +285,6 @@ extern mozilla::LazyLogModule gSHIPBFCacheLog;
 const char kAppstringsBundleURL[] =
     "chrome://global/locale/appstrings.properties";
 
-static void FavorPerformanceHint(bool aPerfOverStarvation) {
-  nsCOMPtr<nsIAppShell> appShell = do_GetService(kAppShellCID);
-  if (appShell) {
-    appShell->FavorPerformanceHint(
-        aPerfOverStarvation,
-        Preferences::GetUint("docshell.event_starvation_delay_hint",
-                             NS_EVENT_STARVATION_DELAY_HINT));
-  }
-}
-
 static bool IsTopLevelDoc(BrowsingContext* aBrowsingContext,
                           nsILoadInfo* aLoadInfo) {
   MOZ_ASSERT(aBrowsingContext);
@@ -6470,14 +6448,6 @@ nsresult nsDocShell::EndPageLoad(nsIWebProgress* aProgress,
     mIsExecutingOnLoadHandler = false;
 
     mEODForCurrentDocument = true;
-
-    // If all documents have completed their loading
-    // favor native event dispatch priorities
-    // over performance
-    if (--gNumberOfDocumentsLoading == 0) {
-      // Hint to use normal native event dispatch priorities
-      FavorPerformanceHint(false);
-    }
   }
   /* Check if the httpChannel has any cache-control related response headers,
    * like no-store, no-cache. If so, update SHEntry so that
@@ -7615,12 +7585,6 @@ nsresult nsDocShell::RestoreFromHistory() {
   mSavingOldViewer = false;
   mEODForCurrentDocument = false;
 
-  // Tell the event loop to favor plevents over user events, see comments
-  // in CreateContentViewer.
-  if (++gNumberOfDocumentsLoading == 1) {
-    FavorPerformanceHint(true);
-  }
-
   if (document) {
     RefPtr<nsDocShell> parent = GetInProcessParentDocshell();
     if (parent) {
@@ -8112,16 +8076,6 @@ nsresult nsDocShell::CreateContentViewer(const nsACString& aContentType,
     }
   }
 
-  // Give hint to native plevent dispatch mechanism. If a document
-  // is loading the native plevent dispatch mechanism should favor
-  // performance over normal native event dispatch priorities.
-  if (++gNumberOfDocumentsLoading == 1) {
-    // Hint to favor performance for the plevent notification mechanism.
-    // We want the pages to load as fast as possible even if its means
-    // native messages might be starved.
-    FavorPerformanceHint(true);
-  }
-
   if (errorOnLocationChangeNeeded) {
     FireOnLocationChange(this, failedChannel, failedURI,
                          LOCATION_CHANGE_ERROR_PAGE);

dom/base/nsContentSink.cpp

@@ -172,7 +172,6 @@ nsresult nsContentSink::Init(Document* aDoc, nsIURI* aURI,
 
   if (StaticPrefs::content_sink_enable_perf_mode() != 0) {
     mDynamicLowerValue = StaticPrefs::content_sink_enable_perf_mode() == 1;
-    FavorPerformanceHint(!mDynamicLowerValue, 0);
   }
 
   return NS_OK;
@@ -731,14 +730,6 @@ nsresult nsContentSink::DidProcessATokenImpl() {
 
 //----------------------------------------------------------------------
 
-void nsContentSink::FavorPerformanceHint(bool perfOverStarvation,
-                                         uint32_t starvationDelay) {
-  static NS_DEFINE_CID(kAppShellCID, NS_APPSHELL_CID);
-  nsCOMPtr<nsIAppShell> appShell = do_GetService(kAppShellCID);
-  if (appShell)
-    appShell->FavorPerformanceHint(perfOverStarvation, starvationDelay);
-}
-
 void nsContentSink::BeginUpdate(Document* aDocument) {
   // Remember nested updates from updates that we started.
   if (mInNotification > 0 && mUpdatesInNotification < 2) {
@@ -811,12 +802,6 @@ void nsContentSink::DropParserAndPerfHint(void) {
   RefPtr<nsParserBase> kungFuDeathGrip = std::move(mParser);
   mozilla::Unused << kungFuDeathGrip;
 
-  if (mDynamicLowerValue) {
-    // Reset the performance hint which was set to FALSE
-    // when mDynamicLowerValue was set.
-    FavorPerformanceHint(true, 0);
-  }
-
   // Call UnblockOnload only if mRunsToComletion is false and if
   // we have already started loading because it's possible that this function
   // is called (i.e. the parser is terminated) before we start loading due to
@@ -857,7 +842,6 @@ nsresult nsContentSink::WillParseImpl(void) {
                             StaticPrefs::content_sink_interactive_time());
 
     if (mDynamicLowerValue != newDynLower) {
-      FavorPerformanceHint(!newDynLower, 0);
       mDynamicLowerValue = newDynLower;
     }
   }

dom/base/nsContentSink.h

@@ -170,8 +170,6 @@ class nsContentSink : public nsICSSLoaderObserver,
   Document* GetDocument() { return mDocument; }
 
  protected:
-  void FavorPerformanceHint(bool perfOverStarvation, uint32_t starvationDelay);
-
   inline int32_t GetNotificationInterval() {
     if (mDynamicLowerValue) {
       return 1000;