Random clean up of SVGResourcesCache

Source/core/svg/SVGDocumentExtensions.h

Index: Source/core/svg/SVGDocumentExtensions.h
diff --git a/Source/core/svg/SVGDocumentExtensions.h b/Source/core/svg/SVGDocumentExtensions.h
index 04214ad3e87b7b635d8186107d7816c1ea8f8ecc..013726fa0b7b20e5db5167ccafd76032f720bcda 100644
--- a/Source/core/svg/SVGDocumentExtensions.h
+++ b/Source/core/svg/SVGDocumentExtensions.h
@@ -60,7 +60,7 @@ public:
     void reportWarning(const String&);
     void reportError(const String&);
 
-    SVGResourcesCache* resourcesCache() const { return m_resourcesCache.get(); }
+    SVGResourcesCache& resourcesCache() const { return *m_resourcesCache; }

[f(malita), 2015/08/19 13:04:34]

Nit: can we store m_resourcesCache inline (instead of an OwnPtr)? Then this
getter would look more natural.

Also, it would be nice to return a const ref here, but if some clients depend on
non-const then don't worry about it - let's leave fixing world const-correctness
for another day :)

[fs, 2015/08/19 13:13:58]

Yeah, it's not too burdensome - I'll do that in a followup.
The way this is currently used, I don't think a const ref. would work - the
actual map this keeps is mutated. We could have one const and one non-const, but
I think the former would never be used (we always access it through non-const
SVGDocumentExtentsions AFAICR.)

 
     void addSVGRootWithRelativeLengthDescendents(SVGSVGElement*);
     void removeSVGRootWithRelativeLengthDescendents(SVGSVGElement*);