Bug 1370412 - Part 0. Add imgIContainer::GetNativeSizesLength to determine a ceiling on the maximum number of expected, unique surfaces. r=tnikkel

image/DynamicImage.cpp

@@ -134,6 +134,12 @@ DynamicImage::GetNativeSizes(nsTArray<IntSize>& aNativeSizes) const
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
+size_t
+DynamicImage::GetNativeSizesLength() const
+{
+  return 0;
+}
+
 NS_IMETHODIMP
 DynamicImage::GetIntrinsicSize(nsSize* aSize)
 {

image/DynamicImage.h

@@ -32,6 +32,7 @@ public:
 
   // Inherited methods from Image.
   nsresult GetNativeSizes(nsTArray<gfx::IntSize>& aNativeSizes) const override;
+  size_t GetNativeSizesLength() const override;
   virtual already_AddRefed<ProgressTracker> GetProgressTracker() override;
   virtual size_t SizeOfSourceWithComputedFallback(
                                  SizeOfState& aState) const override;

image/ImageWrapper.cpp

@@ -145,6 +145,12 @@ ImageWrapper::GetNativeSizes(nsTArray<IntSize>& aNativeSizes) const
   return mInnerImage->GetNativeSizes(aNativeSizes);
 }
 
+size_t
+ImageWrapper::GetNativeSizesLength() const
+{
+  return mInnerImage->GetNativeSizesLength();
+}
+
 NS_IMETHODIMP
 ImageWrapper::GetIntrinsicSize(nsSize* aSize)
 {

image/ImageWrapper.h

@@ -23,6 +23,7 @@ public:
 
   // Inherited methods from Image.
   nsresult GetNativeSizes(nsTArray<gfx::IntSize>& aNativeSizes) const override;
+  size_t GetNativeSizesLength() const override;
   virtual already_AddRefed<ProgressTracker> GetProgressTracker() override;
 
   virtual size_t

image/RasterImage.cpp

@@ -241,6 +241,21 @@ RasterImage::GetNativeSizes(nsTArray<IntSize>& aNativeSizes) const
   return NS_OK;
 }
 
+//******************************************************************************
+size_t
+RasterImage::GetNativeSizesLength() const
+{
+  if (mError || !mHasSize) {
+    return 0;
+  }
+
+  if (mNativeSizes.IsEmpty()) {
+    return 1;
+  }
+
+  return mNativeSizes.Length();
+}
+
 //******************************************************************************
 NS_IMETHODIMP
 RasterImage::GetIntrinsicSize(nsSize* aSize)

image/RasterImage.h

@@ -161,6 +161,7 @@ public:
 #endif
 
   nsresult GetNativeSizes(nsTArray<gfx::IntSize>& aNativeSizes) const override;
+  size_t GetNativeSizesLength() const override;
   virtual nsresult StartAnimation() override;
   virtual nsresult StopAnimation() override;
 

image/VectorImage.cpp

@@ -528,6 +528,13 @@ VectorImage::GetNativeSizes(nsTArray<IntSize>& aNativeSizes) const
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
+//******************************************************************************
+size_t
+VectorImage::GetNativeSizesLength() const
+{
+  return 0;
+}
+
 //******************************************************************************
 NS_IMETHODIMP_(void)
 VectorImage::RequestRefresh(const TimeStamp& aTime)

image/VectorImage.h

@@ -35,6 +35,7 @@ public:
 
   // Methods inherited from Image
   nsresult GetNativeSizes(nsTArray<gfx::IntSize>& aNativeSizes) const override;
+  size_t GetNativeSizesLength() const override;
   virtual size_t SizeOfSourceWithComputedFallback(SizeOfState& aState)
     const override;
   virtual void CollectSizeOfSurfaces(nsTArray<SurfaceMemoryCounter>& aCounters,

image/imgIContainer.idl

@@ -565,5 +565,7 @@ interface imgIContainer : nsISupports
    * Get the set of sizes the image can decode to natively.
    */
   virtual nsresult GetNativeSizes(nsTArray<nsIntSize>& aNativeSizes) const = 0;
+
+  virtual size_t GetNativeSizesLength() const = 0;
   %}
 };