Forward handling of low-mem message to the content renderer client. Add APIs to handle this case.

chrome/renderer/spellchecker/spellcheck.h

Index: chrome/renderer/spellchecker/spellcheck.h
diff --git a/chrome/renderer/spellchecker/spellcheck.h b/chrome/renderer/spellchecker/spellcheck.h
index 28b950762017766c178bef81b8fd28236415d75c..379789febda64fcfd52102f2d51940256bd8abae 100644
--- a/chrome/renderer/spellchecker/spellcheck.h
+++ b/chrome/renderer/spellchecker/spellcheck.h
@@ -21,6 +21,10 @@
 
 class Hunspell;
 
+namespace chrome {
+class ChromeContentRendererClient;
+}
+
 namespace file_util {
 class MemoryMappedFile;
 }
@@ -29,7 +33,7 @@ class MemoryMappedFile;
 // See http://crbug.com/73699.
 class SpellCheck : public RenderProcessObserver {
  public:
-  SpellCheck();
+  explicit SpellCheck(chrome::ChromeContentRendererClient* renderer_client);
   virtual ~SpellCheck();
 
   void Init(base::PlatformFile file,
@@ -135,6 +139,10 @@ class SpellCheck : public RenderProcessObserver {
   // spelling of a word.
   bool initialized_;
 
+  // Reference to the renderer client, for resetting the spellchecker on low-mem
+  // event. Weak reference.
+  chrome::ChromeContentRendererClient* renderer_client_;
+
   DISALLOW_COPY_AND_ASSIGN(SpellCheck);
 };