Bug 1458270: Clean up in the shutdown observer. r=milan a=jcristau

--HG--
extra : amend_source : 7b1277a18a3ed4f441deef8b51cb4ec4dde614cc

widget/GfxInfoBase.cpp

@@ -43,6 +43,7 @@ using mozilla::MutexAutoLock;
 
 nsTArray<GfxDriverInfo>* GfxInfoBase::mDriverInfo;
 bool GfxInfoBase::mDriverInfoObserverInitialized;
+bool GfxInfoBase::mShutdownOccurred;
 
 // Observes for shutdown so that the child GfxDriverInfo list is freed.
 class ShutdownObserver : public nsIObserver
@@ -62,11 +63,17 @@ public:
     delete GfxInfoBase::mDriverInfo;
     GfxInfoBase::mDriverInfo = nullptr;
 
-    for (uint32_t i = 0; i < DeviceFamilyMax; i++)
+    for (uint32_t i = 0; i < DeviceFamilyMax; i++) {
       delete GfxDriverInfo::mDeviceFamilies[i];
+      GfxDriverInfo::mDeviceFamilies[i] = nullptr;
+    }
 
-    for (uint32_t i = 0; i < DeviceVendorMax; i++)
+    for (uint32_t i = 0; i < DeviceVendorMax; i++) {
       delete GfxDriverInfo::mDeviceVendors[i];
+      GfxDriverInfo::mDeviceVendors[i] = nullptr;
+    }
+
+    GfxInfoBase::mShutdownOccurred = true;
 
     return NS_OK;
   }
@@ -855,6 +862,13 @@ GfxInfoBase::GetFeatureStatusImpl(int32_t aFeature,
     return NS_OK;
   }
 
+  if (mShutdownOccurred) {
+    // This is futile; we've already commenced shutdown and our blocklists have
+    // been deleted. We may want to look into resurrecting the blocklist instead
+    // but for now, just don't even go there.
+    return NS_OK;
+  }
+
   // If an operating system was provided by the derived GetFeatureStatusImpl,
   // grab it here. Otherwise, the OS is unknown.
   OperatingSystem os = (aOS ? *aOS : OperatingSystem::Unknown);

widget/GfxInfoBase.h

@@ -77,6 +77,7 @@ public:
 
   static nsTArray<GfxDriverInfo>* mDriverInfo;
   static bool mDriverInfoObserverInitialized;
+  static bool mShutdownOccurred;
 
   virtual nsString Model() { return EmptyString(); }
   virtual nsString Hardware() { return EmptyString(); }

widget/GfxInfoX11.cpp

@@ -268,8 +268,6 @@ GfxInfo::GetFeatureStatusImpl(int32_t aFeature,
                               OperatingSystem* aOS /* = nullptr */)
 
 {
-  GetData();
-
   NS_ENSURE_ARG_POINTER(aStatus);
   *aStatus = nsIGfxInfo::FEATURE_STATUS_UNKNOWN;
   aSuggestedDriverVersion.SetIsVoid(true);
@@ -277,6 +275,12 @@ GfxInfo::GetFeatureStatusImpl(int32_t aFeature,
   if (aOS)
     *aOS = os;
 
+  if (mShutdownOccurred) {
+    return NS_OK;
+  }
+
+  GetData();
+
   if (mGLMajorVersion == 1) {
     // We're on OpenGL 1. In most cases that indicates really old hardware.
     // We better block them, rather than rely on them to fail gracefully, because they don't!

widget/android/GfxInfo.cpp

@@ -377,6 +377,10 @@ GfxInfo::GetFeatureStatusImpl(int32_t aFeature,
   if (aOS)
     *aOS = os;
 
+  if (mShutdownOccurred) {
+    return NS_OK;
+  }
+
   // OpenGL layers are never blacklisted on Android.
   // This early return is so we avoid potentially slow
   // GLStrings initialization on startup when we initialize GL layers.

widget/cocoa/GfxInfo.mm

@@ -308,6 +308,10 @@ GfxInfo::GetFeatureStatusImpl(int32_t aFeature,
   if (aOS)
     *aOS = os;
 
+  if (mShutdownOccurred) {
+    return NS_OK;
+  }
+
   // Don't evaluate special cases when we're evaluating the downloaded blocklist.
   if (!aDriverInfo.Length()) {
     if (aFeature == nsIGfxInfo::FEATURE_WEBGL_MSAA) {

widget/uikit/GfxInfo.cpp

@@ -175,6 +175,10 @@ GfxInfo::GetFeatureStatusImpl(int32_t aFeature,
   if (aOS)
     *aOS = OperatingSystem::Ios;
 
+  if (mShutdownOccurred) {
+    return NS_OK;
+  }
+
   // OpenGL layers are never blacklisted on iOS.
   // This early return is so we avoid potentially slow
   // GLStrings initialization on startup when we initialize GL layers.

widget/windows/GfxInfo.cpp

@@ -1163,6 +1163,10 @@ GfxInfo::GetFeatureStatusImpl(int32_t aFeature,
   if (aOS)
     *aOS = os;
 
+  if (mShutdownOccurred) {
+    return NS_OK;
+  }
+
   // Don't evaluate special cases if we're checking the downloaded blocklist.
   if (!aDriverInfo.Length()) {
     nsAutoString adapterVendorID;