Bug 1543761 - stop reading chrome.manifest files in the app/gre dirs when using omni.ja, r=glandium

Differential Revision: https://phabricator.services.mozilla.com/D29287

--HG--
extra : moz-landing-system : lando

browser/base/content/test/performance/browser_startup_content_mainthreadio.js

@@ -73,18 +73,6 @@ const processes = {
       condition: !WIN, // Visible on Windows with an open marker
       stat: 1,
     },
-    { // bug 1543761
-      path: "GreD:chrome.manifest",
-      condition: !WIN, // Visible on Windows with an open marker
-      stat: 1,
-      close: 1,
-    },
-    { // bug 1376994, bug 1543761
-      path: "XCurProcD:chrome.manifest",
-      condition: !WIN, // Visible on Windows with an open marker
-      stat: 1,
-      close: 1,
-    },
     { // Exists call in ScopedXREEmbed::SetAppDir
       path: "XCurProcD:",
       condition: WIN,
@@ -112,18 +100,6 @@ const processes = {
       condition: !WIN, // Visible on Windows with an open marker
       stat: 1,
     },
-    { // bug 1543761
-      path: "GreD:chrome.manifest",
-      condition: !WIN, // Visible on Windows with an open marker
-      stat: 1,
-      close: 1,
-    },
-    { // bug 1376994, bug 1543761
-      path: "XCurProcD:chrome.manifest",
-      condition: !WIN, // Visible on Windows with an open marker
-      stat: 1,
-      close: 1,
-    },
     { // Exists call in ScopedXREEmbed::SetAppDir
       path: "XCurProcD:",
       condition: WIN,
@@ -146,18 +122,6 @@ const processes = {
       condition: !WIN, // Visible on Windows with an open marker
       stat: 1,
     },
-    { // bug 1543761
-      path: "GreD:chrome.manifest",
-      condition: !WIN, // Visible on Windows with an open marker
-      stat: 1,
-      close: 1,
-    },
-    { // bug 1376994, bug 1543761
-      path: "XCurProcD:chrome.manifest",
-      condition: !WIN, // Visible on Windows with an open marker
-      stat: 1,
-      close: 1,
-    },
     { // Exists call in ScopedXREEmbed::SetAppDir
       path: "XCurProcD:",
       condition: WIN,

browser/base/content/test/performance/browser_startup_mainthreadio.js

@@ -200,18 +200,6 @@ const startupPhases = {
       read: 1,
       close: 1,
     },
-    { // bug 1543761
-      path: "GreD:chrome.manifest",
-      condition: !WIN, // Visible on Windows with an open marker
-      stat: 1,
-      close: 1,
-    },
-    { // bug 1376994, bug 1543761
-      path: "XCurProcD:chrome.manifest",
-      condition: !WIN, // Visible on Windows with an open marker
-      stat: 1,
-      close: 1,
-    },
     { // At least the read seems unavoidable
       path: "PrefD:prefs.js",
       stat: 1,

xpcom/components/nsComponentManager.cpp

@@ -496,32 +496,19 @@ nsresult nsComponentManagerImpl::Init() {
 
     // The overall order in which chrome.manifests are expected to be treated
     // is the following:
-    // - greDir
-    // - greDir's omni.ja
-    // - appDir
-    // - appDir's omni.ja
+    // - greDir's omni.ja or greDir
+    // - appDir's omni.ja or appDir
 
     InitializeModuleLocations();
     ComponentLocation* cl = sModuleLocations->AppendElement();
-    nsCOMPtr<nsIFile> lf =
-        CloneAndAppend(greDir, NS_LITERAL_CSTRING("chrome.manifest"));
     cl->type = NS_APP_LOCATION;
-    cl->location.Init(lf);
-
     RefPtr<nsZipArchive> greOmnijar =
         mozilla::Omnijar::GetReader(mozilla::Omnijar::GRE);
     if (greOmnijar) {
-      cl = sModuleLocations->AppendElement();
-      cl->type = NS_APP_LOCATION;
       cl->location.Init(greOmnijar, "chrome.manifest");
-    }
-
-    bool equals = false;
-    appDir->Equals(greDir, &equals);
-    if (!equals) {
-      cl = sModuleLocations->AppendElement();
-      cl->type = NS_APP_LOCATION;
-      lf = CloneAndAppend(appDir, NS_LITERAL_CSTRING("chrome.manifest"));
+    } else {
+      nsCOMPtr<nsIFile> lf =
+          CloneAndAppend(greDir, NS_LITERAL_CSTRING("chrome.manifest"));
       cl->location.Init(lf);
     }
 
@@ -531,6 +518,16 @@ nsresult nsComponentManagerImpl::Init() {
       cl = sModuleLocations->AppendElement();
       cl->type = NS_APP_LOCATION;
       cl->location.Init(appOmnijar, "chrome.manifest");
+    } else {
+      bool equals = false;
+      appDir->Equals(greDir, &equals);
+      if (!equals) {
+        cl = sModuleLocations->AppendElement();
+        cl->type = NS_APP_LOCATION;
+        nsCOMPtr<nsIFile> lf =
+            CloneAndAppend(appDir, NS_LITERAL_CSTRING("chrome.manifest"));
+        cl->location.Init(lf);
+      }
     }
 
     RereadChromeManifests(false);