streamline web documentation

This is the next step in reducing the amount of typing
in bookmaker, and presenting a web-base interface that
more closely matches the include documentation.

Moving towards making xxx_Reference solely contain
use documentation, and xxx_Overview (unpublished)
contain theory of operation documentation.

Fixed quite a few bugs along the way, and made
function and member documentation tighter.

TBR=caryclark@google.com
Docs-Preview: https://skia.org/?cl=160640
Change-Id: I763df4d59baa5dfd0177f0523294b5316434c4b0
Reviewed-on: https://skia-review.googlesource.com/c/160640
Reviewed-by: Cary Clark <caryclark@skia.org>
Commit-Queue: Cary Clark <caryclark@skia.org>
Auto-Submit: Cary Clark <caryclark@skia.org>
diff --git a/docs/SkImage_Reference.bmh b/docs/SkImage_Reference.bmh
index 2a8f35d..7ca584a 100644
--- a/docs/SkImage_Reference.bmh
+++ b/docs/SkImage_Reference.bmh
@@ -134,7 +134,7 @@
 #Line # parameter type for MakeFromRaster ##
 
 #Code
-typedef void* ReleaseContext;
+#Populate
 ##
 
 Caller data passed to RasterReleaseProc; may be nullptr.
@@ -147,7 +147,7 @@
 #Line #  parameter type for MakeFromRaster ##
 
 #Code
-typedef void (*RasterReleaseProc)(const void* pixels, ReleaseContext);
+#Populate
 ##
 
 Function called when Image no longer shares pixels. ReleaseContext is
@@ -340,7 +340,7 @@
 #Line # parameter type for MakeFromTexture ##
 
 #Code
-typedef void (*TextureReleaseProc)(ReleaseContext releaseContext);
+#Populate
 ##
 
 User function called when supplied texture may be deleted.
@@ -855,10 +855,7 @@
 #EnumClass BitDepth
 #Line # options for MakeFromPicture ##
 #Code
-    enum class BitDepth {
-        kU8,
-        kF16,
-    };
+#Populate
 ##
 
 #Const kU8 0
@@ -1538,10 +1535,7 @@
 #Enum CachingHint
 #Line # options for readPixels and scalePixels ##
 #Code
-    enum CachingHint {
-        kAllow_CachingHint,
-        kDisallow_CachingHint,
-    };
+#Populate
 ##
 
 CachingHint selects whether Skia may internally cache Bitmaps generated by
@@ -2115,7 +2109,7 @@
 #Line # parameter type for MakeBackendTextureFromSkImage ##
 
 #Code
-typedef std::function<void(GrBackendTexture)> BackendTextureReleaseProc;
+#Populate
 ##
 
 Defines a callback function, taking one parameter of type GrBackendTexture with
@@ -2197,9 +2191,7 @@
 #Enum LegacyBitmapMode
 #Deprecated soon
 #Code
-    enum LegacyBitmapMode {
-        kRO_LegacyBitmapMode,
-    };
+#Populate
 ##
 
 #Const kRO_LegacyBitmapMode 0