Bug 1761432 - Part 2: Split out script load request state for when we require loading from source r=smaug

This is used when we explicitly don't want to load cached bytecode. It is
better served by a separate flag in the request than a state.

Differential Revision: https://phabricator.services.mozilla.com/D142042

dom/script/ScriptLoadHandler.cpp

@@ -294,7 +294,7 @@ nsresult ScriptLoadHandler::EnsureKnownDataType(
   MOZ_ASSERT(req, "StreamLoader's request went away prematurely");
   NS_ENSURE_SUCCESS(rv, rv);
 
-  if (mRequest->IsLoadingSource()) {
+  if (mRequest->mFetchSourceOnly) {
     mRequest->SetTextSource();
     TRACE_FOR_TEST(mRequest->mLoadContext->GetScriptElement(),
                    "scriptloader_load_source");

dom/script/ScriptLoader.cpp

@@ -255,6 +255,8 @@ ScriptLoader::~ScriptLoader() {
 static void CollectScriptTelemetry(ScriptLoadRequest* aRequest) {
   using namespace mozilla::Telemetry;
 
+  MOZ_ASSERT(aRequest->IsLoading());
+
   // Skip this function if we are not running telemetry.
   if (!CanRecordExtended()) {
     return;
@@ -270,14 +272,13 @@ static void CollectScriptTelemetry(ScriptLoadRequest* aRequest) {
   // Report the type of source. This is used to monitor the status of the
   // JavaScript Start-up Bytecode Cache, with the expectation of an almost zero
   // source-fallback and alternate-data being roughtly equal to source loads.
-  if (aRequest->IsLoadingSource()) {
+  if (aRequest->mFetchSourceOnly) {
     if (aRequest->GetLoadContext()->mIsInline) {
       AccumulateCategorical(LABELS_DOM_SCRIPT_LOADING_SOURCE::Inline);
     } else if (aRequest->IsTextSource()) {
       AccumulateCategorical(LABELS_DOM_SCRIPT_LOADING_SOURCE::SourceFallback);
     }
   } else {
-    MOZ_ASSERT(aRequest->IsLoading());
     if (aRequest->IsTextSource()) {
       AccumulateCategorical(LABELS_DOM_SCRIPT_LOADING_SOURCE::Source);
     } else if (aRequest->IsBytecode()) {
@@ -486,7 +487,7 @@ nsresult ScriptLoader::RestartLoad(ScriptLoadRequest* aRequest) {
 
   // Start a new channel from which we explicitly request to stream the source
   // instead of the bytecode.
-  aRequest->mState = ScriptLoadRequest::State::FetchingSource;
+  aRequest->mFetchSourceOnly = true;
   nsresult rv;
   if (aRequest->IsModuleRequest()) {
     rv = mModuleLoader->RestartModuleLoad(aRequest);
@@ -596,7 +597,7 @@ nsresult ScriptLoader::StartLoadInternal(ScriptLoadRequest* aRequest,
   if (cic && StaticPrefs::dom_script_loader_bytecode_cache_enabled()) {
     MOZ_ASSERT(!aRequest->GetLoadContext()->GetWebExtGlobal(),
                "Can not bytecode cache WebExt code");
-    if (!aRequest->IsLoadingSource()) {
+    if (!aRequest->mFetchSourceOnly) {
       // Inform the HTTP cache that we prefer to have information coming from
       // the bytecode cache instead of the sources, if such entry is already
       // registered.
@@ -1078,7 +1079,7 @@ bool ScriptLoader::ProcessInlineScript(nsIScriptElement* aElement,
                         referrerPolicy);
   request->GetLoadContext()->mIsInline = true;
   request->GetLoadContext()->mLineNo = aElement->GetScriptLineNumber();
-  request->mState = ScriptLoadRequest::State::FetchingSource;
+  request->mFetchSourceOnly = true;
   request->SetTextSource();
   TRACE_FOR_TEST_BOOL(request->GetLoadContext()->GetScriptElement(),
                       "scriptloader_load_source");

js/loader/ScriptLoadRequest.cpp

@@ -84,6 +84,7 @@ ScriptLoadRequest::ScriptLoadRequest(ScriptKind aKind, nsIURI* aURI,
     : mKind(aKind),
       mIsCanceled(false),
       mState(State::Fetching),
+      mFetchSourceOnly(false),
       mDataType(DataType::eUnknown),
       mFetchOptions(aFetchOptions),
       mIntegrity(aIntegrity),

js/loader/ScriptLoadRequest.h

@@ -184,20 +184,11 @@ class ScriptLoadRequest
 
   virtual void SetReady();
 
-  enum class State : uint8_t {
-    Fetching,        // Request either source or bytecode
-    FetchingSource,  // Explicitly request source stream
-    Compiling,
-    LoadingImports,
-    Ready
-  };
+  enum class State : uint8_t { Fetching, Compiling, LoadingImports, Ready };
 
   bool IsReadyToRun() const { return mState == State::Ready; }
-  bool IsLoading() const {
-    return mState == State::Fetching || mState == State::FetchingSource;
-  }
 
-  bool IsLoadingSource() const { return mState == State::FetchingSource; }
+  bool IsLoading() const { return mState == State::Fetching; }
 
   bool InCompilingStage() const { return mState == State::Compiling; }
 
@@ -297,6 +288,7 @@ class ScriptLoadRequest
 
   bool mIsCanceled;    // True if we have been explicitly canceled.
   State mState;        // Are we still waiting for a load to complete?
+  bool mFetchSourceOnly;  // Request source, not cached bytecode.
   DataType mDataType;  // Does this contain Source or Bytecode?
   RefPtr<ScriptFetchOptions> mFetchOptions;
   const SRIMetadata mIntegrity;