Bug 1061713 - Don't crash release builds if a D3D TextureClient is unlocked without being locked. r=Bas

gfx/layers/d3d11/TextureD3D11.cpp

@@ -264,6 +264,9 @@ void
 TextureClientD3D11::Unlock()
 {
   MOZ_ASSERT(mIsLocked, "Unlocked called while the texture is not locked!");
+  if (!mIsLocked) {
+    return;
+  }
 
   if (mDrawTarget) {
     // see the comment on TextureClient::BorrowDrawTarget.

gfx/layers/d3d9/TextureD3D9.cpp

@@ -631,6 +631,10 @@ void
 CairoTextureClientD3D9::Unlock()
 {
   MOZ_ASSERT(mIsLocked, "Unlocked called while the texture is not locked!");
+  if (!mIsLocked) {
+    return;
+  }
+
   if (mDrawTarget) {
     mDrawTarget->Flush();
     mDrawTarget = nullptr;