Improve performance with image masks (bug 857031)

- it aims to partially fix performance issue reported: https://bugzilla.mozilla.org/show_bug.cgi?id=857031;
- the idea is too avoid to use byte arrays but use ImageBitmap which are a way faster to draw:
  * an ImageBitmap is Transferable which means that it can be built in the worker instead of in the main thread:
    - this is achieved in using an OffscreenCanvas when it's available, there is a bug to enable them
      for pdf.js: https://bugzilla.mozilla.org/show_bug.cgi?id=1763330;
    - or in using createImageBitmap: in Firefox a task is sent to the main thread to build the bitmap so
      it's slightly slower than using an OffscreenCanvas.
  * it's transfered from the worker to the main thread by "reference";
  * the byte buffers used to create the image data have a very short lifetime and ergo the memory used is globally
    less than before.
- Use the localImageCache for the mask;
- Fix the pdf issue4436r.pdf: it was expected to have a binary stream for the image;
- Move the singlePixel trick from operator_list to image: this way we can use this trick even if it isn't in a set
  as defined in operator_list.

src/core/evaluator.js

@@ -540,7 +540,7 @@ class PartialEvaluator {
   }
 
   _sendImgData(objId, imgData, cacheGlobally = false) {
-    const transfers = imgData ? [imgData.data.buffer] : null;
+    const transfers = imgData ? [imgData.bitmap || imgData.data.buffer] : null;
 
     if (this.parsingType3Font || cacheGlobally) {
       return this.handler.send(
@@ -612,6 +612,33 @@ class PartialEvaluator {
       );
       const decode = dict.getArray("D", "Decode");
 
+      if (this.parsingType3Font) {
+        imgData = PDFImage.createRawMask({
+          imgArray,
+          width: w,
+          height: h,
+          imageIsFromDecodeStream: image instanceof DecodeStream,
+          inverseDecode: !!decode && decode[0] > 0,
+          interpolate,
+        });
+
+        imgData.cached = !!cacheKey;
+        args = [imgData];
+
+        operatorList.addOp(OPS.paintImageMaskXObject, args);
+        if (cacheKey) {
+          localImageCache.set(cacheKey, imageRef, {
+            fn: OPS.paintImageMaskXObject,
+            args,
+          });
+        }
+
+        if (optionalContent !== undefined) {
+          operatorList.addOp(OPS.endMarkedContent, []);
+        }
+        return;
+      }
+
       imgData = PDFImage.createMask({
         imgArray,
         width: w,
@@ -620,8 +647,36 @@ class PartialEvaluator {
         inverseDecode: !!decode && decode[0] > 0,
         interpolate,
       });
-      imgData.cached = !!cacheKey;
-      args = [imgData];
+
+      if (imgData.isSingleOpaquePixel) {
+        // Handles special case of mainly LaTeX documents which use image
+        // masks to draw lines with the current fill style.
+        operatorList.addOp(OPS.paintSolidColorImageMask, []);
+        if (cacheKey) {
+          localImageCache.set(cacheKey, imageRef, {
+            fn: OPS.paintSolidColorImageMask,
+            args: [],
+          });
+        }
+
+        if (optionalContent !== undefined) {
+          operatorList.addOp(OPS.endMarkedContent, []);
+        }
+        return;
+      }
+
+      const objId = `mask_${this.idFactory.createObjId()}`;
+      operatorList.addDependency(objId);
+      this._sendImgData(objId, imgData);
+
+      args = [
+        {
+          data: objId,
+          width: imgData.width,
+          height: imgData.height,
+          interpolate: imgData.interpolate,
+        },
+      ];
 
       operatorList.addOp(OPS.paintImageMaskXObject, args);
       if (cacheKey) {