Fix more coverity defects - Uninitialized class fields.

In SkCanvas, SkBitmapCache::Entry, SkDrawLooper

CID=13440,1366,16236,14393

Review URL: http://codereview.appspot.com/4628055

git-svn-id: http://skia.googlecode.com/svn/trunk@1671 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/effects/SkBitmapCache.cpp b/src/effects/SkBitmapCache.cpp
index 2a3f87a..404eace 100644
--- a/src/effects/SkBitmapCache.cpp
+++ b/src/effects/SkBitmapCache.cpp
@@ -24,7 +24,10 @@
     size_t      fSize;
     SkBitmap    fBitmap;
 
-    Entry(const void* buffer, size_t size, const SkBitmap& bm) : fBitmap(bm) {
+    Entry(const void* buffer, size_t size, const SkBitmap& bm)
+            : fPrev(NULL),
+              fNext(NULL),
+              fBitmap(bm) {
         fBuffer = sk_malloc_throw(size);
         fSize = size;
         memcpy(fBuffer, buffer, size);