From 33956e6925a09a8582827b3d69c321c747d18e25 Mon Sep 17 00:00:00 2001
From: Markus Stange <mstange@themasta.com>
Date: Thu, 25 Sep 2014 15:19:28 -0400
Subject: [PATCH] Bug 983241 -  Allow filterNodeSoftware->SetInput(*, nullptr)
 in order to drop reference to input surface / filter. r=Bas

---
 gfx/2d/FilterNodeSoftware.cpp | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/gfx/2d/FilterNodeSoftware.cpp b/gfx/2d/FilterNodeSoftware.cpp
index e4d4ddffbd92..c8bd40add58d 100644
--- a/gfx/2d/FilterNodeSoftware.cpp
+++ b/gfx/2d/FilterNodeSoftware.cpp
@@ -932,7 +932,7 @@ FilterNodeSoftware::~FilterNodeSoftware()
 void
 FilterNodeSoftware::SetInput(uint32_t aIndex, FilterNode *aFilter)
 {
-  if (aFilter->GetBackendType() != FILTER_BACKEND_SOFTWARE) {
+  if (aFilter && aFilter->GetBackendType() != FILTER_BACKEND_SOFTWARE) {
     MOZ_ASSERT(false, "can only take software filters as inputs");
     return;
   }
@@ -955,10 +955,8 @@ FilterNodeSoftware::SetInput(uint32_t aInputEnumIndex,
     MOZ_CRASH();
     return;
   }
-  if ((uint32_t)inputIndex >= mInputSurfaces.size()) {
+  if ((uint32_t)inputIndex >= NumberOfSetInputs()) {
     mInputSurfaces.resize(inputIndex + 1);
-  }
-  if ((uint32_t)inputIndex >= mInputFilters.size()) {
     mInputFilters.resize(inputIndex + 1);
   }
   mInputSurfaces[inputIndex] = aSurface;
@@ -969,6 +967,10 @@ FilterNodeSoftware::SetInput(uint32_t aInputEnumIndex,
     aFilter->AddInvalidationListener(this);
   }
   mInputFilters[inputIndex] = aFilter;
+  if (!aSurface && !aFilter && (size_t)inputIndex == NumberOfSetInputs()) {
+    mInputSurfaces.resize(inputIndex);
+    mInputFilters.resize(inputIndex);
+  }
   Invalidate();
 }