A speculative Revert for r165872 - Remove static thread pointers from CC, attempt 2

cc/font_atlas.cc

Index: cc/font_atlas.cc
===================================================================
--- cc/font_atlas.cc	(revision 165906)
+++ cc/font_atlas.cc	(working copy)
@@ -28,7 +28,7 @@
 
 void FontAtlas::drawText(SkCanvas* canvas, const SkPaint& paint, const std::string& text, const gfx::Point& destPosition, const gfx::Size& clip) const
 {
-    DCHECK(m_threadChecker.CalledOnValidThread());
+    DCHECK(Proxy::isImplThread());
 
     std::vector<std::string> lines;
     base::SplitString(text, '\n', &lines);
@@ -44,7 +44,7 @@
 
 void FontAtlas::drawOneLineOfTextInternal(SkCanvas* canvas, const SkPaint& paint, const std::string& textLine, const gfx::Point& destPosition) const
 {
-    DCHECK(m_threadChecker.CalledOnValidThread());
+    DCHECK(Proxy::isImplThread());
 
     gfx::Point position = destPosition;
     for (unsigned i = 0; i < textLine.length(); ++i) {
@@ -59,7 +59,7 @@
 
 void FontAtlas::drawDebugAtlas(SkCanvas* canvas, const gfx::Point& destPosition) const
 {
-    DCHECK(m_threadChecker.CalledOnValidThread());
+    DCHECK(Proxy::isImplThread());
 
     SkIRect source = SkIRect::MakeWH(m_atlas.width(), m_atlas.height());
     canvas->drawBitmapRect(m_atlas, &source, SkRect::MakeXYWH(destPosition.x(), destPosition.y(), m_atlas.width(), m_atlas.height()));