Added support for CSS filters to the software compositor.

cc/software_renderer.cc

Index: cc/software_renderer.cc
diff --git a/cc/software_renderer.cc b/cc/software_renderer.cc
index 5c31d7b12e9c6c024aa48c7b46d582d9149bce56..ed37af660bda54bdece1d54e469162885d8cf552 100644
--- a/cc/software_renderer.cc
+++ b/cc/software_renderer.cc
@@ -268,6 +268,11 @@ void SoftwareRenderer::drawRenderPassQuad(const DrawingFrame& frame, const Rende
     if (!contentTexture || !contentTexture->id())
         return;
 
+    const RenderPass* renderPass = frame.renderPassesById->get(quad->renderPassId());
+    DCHECK(renderPass);
+    if (!renderPass)
+        return;
+
     DCHECK(isSoftwareResource(contentTexture->id()));
     ResourceProvider::ScopedReadLockSoftware lock(m_resourceProvider, contentTexture->id());
 
@@ -287,6 +292,10 @@ void SoftwareRenderer::drawRenderPassQuad(const DrawingFrame& frame, const Rende
     shader->setLocalMatrix(contentMat);
     m_skCurrentPaint.setShader(shader);
 
+    SkImageFilter* filter = renderPass->filter();
+    if (filter)
+        m_skCurrentPaint.setImageFilter(filter);
+
     if (quad->maskResourceId()) {
         ResourceProvider::ScopedReadLockSoftware maskLock(m_resourceProvider, quad->maskResourceId());