Fix for Multipage selection by dragging mouse in OOP case in PDF.

chrome/browser/resources/pdf/pdf.js

Index: chrome/browser/resources/pdf/pdf.js
diff --git a/chrome/browser/resources/pdf/pdf.js b/chrome/browser/resources/pdf/pdf.js
index fb4d3ee53a3d7d19b7c918089fcc09b3de7097a1..ea49e24f09a761203e665d860a3f7998c8baa80d 100644
--- a/chrome/browser/resources/pdf/pdf.js
+++ b/chrome/browser/resources/pdf/pdf.js
@@ -157,6 +157,10 @@ function PDFViewer(streamDetails) {
   this.paramsParser_ = new OpenPDFParamsParser();
   this.navigator_ = new Navigator(this.streamDetails_.originalUrl,
       this.viewport_, this.paramsParser_);
+  this.isSelecting_ = false;
+  this.mousemoveCallback_ = null;
+  this.timerId_ = null;
+  this.dragDirection_;
 }
 
 PDFViewer.prototype = {
@@ -450,6 +454,105 @@ PDFViewer.prototype = {
       case 'bookmarks':
         this.bookmarks_ = message.data.bookmarks;
         break;
+      case 'setIsSelecting':
+        this.isSelecting_ = message.data.isSelecting;

[Sam McNally, 2015/02/04 02:56:01]

this.isSelecting_ isn't used anywhere else. Remove it.

[Deepak, 2015/02/04 13:50:54]

Done.

+        if (this.isSelecting_) {
+            this.mousemoveCallback_ = this.selectionDragListener_.bind(this);

[Sam McNally, 2015/02/04 02:56:01]

2 space indent.

Also, only set mousemoveCallback_ once.

[Deepak, 2015/02/04 13:50:54]

Done.

+            this.plugin_.addEventListener('mousemove',
+                this.mousemoveCallback_, false);
+        } else {
+            this.plugin_.removeEventListener('mousemove',

[Sam McNally, 2015/02/04 02:56:02]

Ditto.

[Deepak, 2015/02/04 13:50:54]

Done.

+                this.mousemoveCallback_, false);
+            this.clearTimer_();
+        }
+        break;
+    }
+  },
+
+  /**
+   * @private
+   * Clear the timer if it is active and reset timerId.
+   */
+  clearTimer_: function() {
+    if (this.timerId_) {
+      window.clearTimeout(this.timerId_);

[Sam McNally, 2015/02/04 02:56:01]

Use clearInterval here.

[Deepak, 2015/02/04 13:50:54]

Done.

+      this.timerId_ = null;
+    }
+  },
+
+  /**
+   * @private
+   * Handles scrolling in the page when we drag mouse out of the viewport and
+   * does not move mouse, Then no mouse move event came so we are scrolling
+   * based on timer in drag direction.
+   */
+  dragScrollPage_: function() {
+    this.clearTimer_();
+    var position = this.viewport_.position;
+    switch (this.dragDirection_) {
+        case 'up':
+            position.y -= ((Viewport.SCROLL_INCREMENT) / this.viewport_.zoom);
+            break;
+        case 'down':
+            position.y += ((Viewport.SCROLL_INCREMENT) / this.viewport_.zoom);
+            break;
+        case 'left':
+            position.x -= ((Viewport.SCROLL_INCREMENT) / this.viewport_.zoom);
+            break;
+        case 'right':
+            position.x += ((Viewport.SCROLL_INCREMENT) / this.viewport_.zoom);
+            break;
+    }
+    this.viewport_.position = position;
+    this.timerId_ = window.setTimeout(this.dragScrollPage_.bind(this), 50);

[Sam McNally, 2015/02/04 02:56:01]

Remove.

[Deepak, 2015/02/04 13:50:54]

Done.

+  },
+
+  /**
+   * @private
+   * Handles mousemove events. Scrolls page when mouse move happen reacting to
+   * the direction of scroll.
+   * @param {Object} event The mouse move event.
+   */
+  selectionDragListener_: function(event) {
+    var position = this.viewport_.position;
+    var viewportRect = {
+      x1: position.x / this.viewport_.zoom,
+      y1: position.y / this.viewport_.zoom,
+      x2: (position.x + this.viewport_.size.width) / this.viewport_.zoom,
+      y2: (position.y + this.viewport_.size.height) / this.viewport_.zoom
+    };
+    var point = {
+      x: event.pageX / this.viewport_.zoom,
+      y: event.pageY / this.viewport_.zoom
+    };
+
+    if ((point.x >= viewportRect.x1 && point.x <= viewportRect.x2) &&
+        (point.y >= viewportRect.y1 && point.y <= viewportRect.y2)) {
+      this.clearTimer_();
+      return;
+    }
+
+    if (this.viewport_.documentHasScrollbars().vertical) {

[Sam McNally, 2015/02/04 02:56:01]

This won't work for diagonal scrolls. Instead, calculate and store a scroll
velocity using
Math.min(Math.max(-event.offsetX,
                  event.offsetX - this.plugin_.offsetWidth, 0),
         100) * Math.sign(event.offsetX);
and similarly for y. Then in dragScrollPage_, add the velocity to the viewport
position.

[Deepak, 2015/02/04 13:50:54]

Done.

+      if (point.y < viewportRect.y1 && viewportRect.y1 > 0) {
+            this.dragDirection_ = 'up';
+            this.dragScrollPage_();

[Sam McNally, 2015/02/04 02:56:01]

Instead of calling dragScrollPage_ here, after calculating the new velocity,
call setInterval if the velocity is non-zero and there isn't already a timer
running. Also call clearTimer_() if the velocity is zero.

[Deepak, 2015/02/04 13:50:54]

Done.

+      } else if ((point.y > viewportRect.y2) &&
+        (event.pageY < (this.viewport_.documentDimensions_.height *
+            this.viewport_.zoom))) {
+            this.dragDirection_ = 'down';
+            this.dragScrollPage_();
+      }
+    }
+    if (this.viewport_.documentHasScrollbars().horizontal) {
+      if (point.x < viewportRect.x1 && viewportRect.x1 > 0) {
+            this.dragDirection_ = 'left';
+            this.dragScrollPage_();
+      } else if ((point.x > viewportRect.x2) &&
+        (event.pageX < this.viewport_.documentDimensions_.width *
+            this.viewport_.zoom)) {
+            this.dragDirection_ = 'right';
+            this.dragScrollPage_();
+      }
     }
   },