Revert "Revert "Revert of https://codereview.chromium.org/110593003/""

This reverts commit 0fef787f33aa38109a0c8427e0098d997efdd5ff.

failed in chrome: https://codereview.chromium.org/124503002/

Review URL: https://codereview.chromium.org/105523008

git-svn-id: http://skia.googlecode.com/svn/trunk@12906 2bbb7eff-a529-9590-31e7-b0007b416f81

3 files changed, 26 insertions, 44 deletions

diff --git a/include/core/SkBitmapDevice.h b/include/core/SkBitmapDevice.h
index f3d40d0ce8..adc8e2b2c1 100644
--- a/include/core/SkBitmapDevice.h
+++ b/include/core/SkBitmapDevice.h
@@ -258,7 +258,8 @@ private:
 
     friend class SkSurface_Raster;
 
-    void init(SkBitmap::Config config, int width, int height, bool isOpaque);
+    // only call from constructor, to try to allocate the pixels
+    void init(SkBitmap::Config, int width, int height, bool isOpaque);
 
     // used to change the backend's pixels (and possibly config/rowbytes)
     // but cannot change the width/height, so there should be no change to
diff --git a/include/core/SkMallocPixelRef.h b/include/core/SkMallocPixelRef.h
index c40afc433a..272dc21fd8 100644
--- a/include/core/SkMallocPixelRef.h
+++ b/include/core/SkMallocPixelRef.h
@@ -32,9 +32,11 @@ public:
 
     /**
      *  Return a new SkMallocPixelRef, automatically allocating storage for the
-     *  pixels. If rowBytes are 0, an optimal value will be chosen automatically.
-     *  If rowBytes is > 0, then it will be respected, or NULL will be returned
-     *  if rowBytes is invalid for the specified info.
+     *  pixels.
+     *
+     *  If rowBytes is 0, an optimal value will be chosen automatically.
+     *  If rowBytes is > 0, then it will be used, unless it is invald for the
+     *  specified info, in which case NULL will be returned (failure).
      *
      *  This pixelref will ref() the specified colortable (if not NULL).
      *
@@ -88,7 +90,7 @@ protected:
     SkMallocPixelRef(SkFlattenableReadBuffer& buffer);
     virtual ~SkMallocPixelRef();
 
-    virtual bool onNewLockPixels(LockRec*) SK_OVERRIDE;
+    virtual void* onLockPixels(SkColorTable**) SK_OVERRIDE;
     virtual void onUnlockPixels() SK_OVERRIDE;
     virtual void flatten(SkFlattenableWriteBuffer&) const SK_OVERRIDE;
     virtual size_t getAllocatedSizeInBytes() const SK_OVERRIDE;
diff --git a/include/core/SkPixelRef.h b/include/core/SkPixelRef.h
index 4811435721..6700eb4def 100644
--- a/include/core/SkPixelRef.h
+++ b/include/core/SkPixelRef.h
@@ -14,11 +14,8 @@
 #include "SkRefCnt.h"
 #include "SkString.h"
 #include "SkFlattenable.h"
-#include "SkImageInfo.h"
 #include "SkTDArray.h"
 
-//#define SK_SUPPORT_LEGACY_ONLOCKPIXELS
-
 #ifdef SK_DEBUG
     /**
      *  Defining SK_IGNORE_PIXELREF_SETPRELOCKED will force all pixelref
@@ -63,11 +60,11 @@ public:
     /** Return the pixel memory returned from lockPixels, or null if the
         lockCount is 0.
     */
-    void* pixels() const { return fRec.fPixels; }
+    void* pixels() const { return fPixels; }
 
     /** Return the current colorTable (if any) if pixels are locked, or null.
     */
-    SkColorTable* colorTable() const { return fRec.fColorTable; }
+    SkColorTable* colorTable() const { return fColorTable; }
 
     /**
      *  To access the actual pixels of a pixelref, it must be "locked".
@@ -92,19 +89,10 @@ public:
 
     SkDEBUGCODE(int getLockCount() const { return fLockCount; })
 
-    /**
-     *  Call to access the pixel memory. Return true on success. Balance this
-     *  with a call to unlockPixels().
-     */
-    bool lockPixels();
-
-    /**
-     *  Call to access the pixel memory. On success, return true and fill out
-     *  the specified rec. On failure, return false and ignore the rec parameter.
-     *  Balance this with a call to unlockPixels().
-     */
-    bool lockPixels(LockRec* rec);
-
+    /** Call to access the pixel memory, which is returned. Balance with a call
+        to unlockPixels().
+    */
+    void lockPixels();
     /** Call to balanace a previous call to lockPixels(). Returns the pixels
         (or null) after the unlock. NOTE: lock calls can be nested, but the
         matching number of unlock calls must be made in order to free the
@@ -261,27 +249,18 @@ public:
     void addGenIDChangeListener(GenIDChangeListener* listener);
 
 protected:
-#ifdef SK_SUPPORT_LEGACY_ONLOCKPIXELS
-    virtual void* onLockPixels(SkColorTable**);
-    virtual bool onNewLockPixels(LockRec*);
-#else
-    /**
-     *  On success, returns true and fills out the LockRec for the pixels. On
-     *  failure returns false and ignores the LockRec parameter.
-     *
-     *  The caller will have already acquired a mutex for thread safety, so this
-     *  method need not do that.
-     */
-    virtual bool onNewLockPixels(LockRec*) = 0;
-#endif
+    /** Called when the lockCount goes from 0 to 1. The caller will have already
+        acquire a mutex for thread safety, so this method need not do that.
+    */
+    virtual void* onLockPixels(SkColorTable**) = 0;
 
     /**
-     *  Balancing the previous successful call to onNewLockPixels. The locked
-     *  pixel address will no longer be referenced, so the subclass is free to
-     *  move or discard that memory.
+     *  Called when the lock count goes from 1 to 0. The caller will have
+     *  already acquire a mutex for thread safety, so this method need not do
+     *  that.
      *
-     *  The caller will have already acquired a mutex for thread safety, so this
-     *  method need not do that.
+     *  If the previous call to onLockPixels failed (i.e. returned NULL), then
+     *  the onUnlockPixels will NOT be called.
      */
     virtual void onUnlockPixels() = 0;
 
@@ -326,15 +305,15 @@ protected:
     // only call from constructor. Flags this to always be locked, removing
     // the need to grab the mutex and call onLockPixels/onUnlockPixels.
     // Performance tweak to avoid those calls (esp. in multi-thread use case).
-    void setPreLocked(void*, size_t rowBytes, SkColorTable*);
+    void setPreLocked(void* pixels, SkColorTable* ctable);
 
 private:
     SkBaseMutex*    fMutex; // must remain in scope for the life of this object
 
     const SkImageInfo fInfo;
 
-    // LockRec is only valid if we're in a locked state (isLocked())
-    LockRec         fRec;
+    void*           fPixels;
+    SkColorTable*   fColorTable;    // we do not track ownership, subclass does
     int             fLockCount;
 
     mutable uint32_t fGenerationID;