Revert of Fix SkTextBlob offset semantics. (patchset #2 id:20001 of https://codereview.chromium.org/605533002/)

Reason for revert:
Breaking the Chrome builds with the error:

[14:54:14.317833] ../../skia/ext/pixel_ref_utils.cc:221:16: error: 'drawPosText' marked 'override' but does not override any member functions
[14:54:14.318022]   virtual void drawPosText(const SkDraw& draw,
[14:54:14.318082]                ^

Original issue's description:
> Fix SkTextBlob offset semantics.
>
> Implement proper x/y drawTextBlob() handling by plumbing a
> drawPosText() offset parameter (to act as an additional glyph pos
> translation) throughout the device layer.
>
> The new offset superceeds the existing constY, with a minor semantic
> tweak: whereas previous implementations were ignoring constY in 2D
> positioning mode (scalarsPerGlyph == 2), now the offset is always
> observed, in all positioning modes. We can do this because existing
> drawPosText() clients always pass constY == 0 for full positioning mode.
>
> R=reed@google.com, jvanverth@google.com, robertphillips@google.com
>
> Committed: https://skia.googlesource.com/skia/+/c13bc571d3e61a43b87eb97f0719abd304cafaf2

R=jvanverth@google.com, reed@google.com, bsalomon@google.com, fmalita@chromium.org
TBR=bsalomon@google.com, fmalita@chromium.org, jvanverth@google.com, reed@google.com
NOTREECHECKS=true
NOTRY=true

Author: robertphillips@google.com

Review URL: https://codereview.chromium.org/609223003
diff --git a/src/gpu/GrStencilAndCoverTextContext.cpp b/src/gpu/GrStencilAndCoverTextContext.cpp
index cfcabe9..c1d9e9d 100644
--- a/src/gpu/GrStencilAndCoverTextContext.cpp
+++ b/src/gpu/GrStencilAndCoverTextContext.cpp
@@ -54,7 +54,7 @@
     // will turn off the use of device-space glyphs when perspective transforms
     // are in use.
 
-    this->init(paint, skPaint, byteLength, kMaxAccuracy_RenderMode, SkPoint::Make(0, 0));
+    this->init(paint, skPaint, byteLength, kMaxAccuracy_RenderMode);
 
     // Transform our starting point.
     if (fNeedsDeviceSpaceGlyphs) {
@@ -123,8 +123,8 @@
                                                const char text[],
                                                size_t byteLength,
                                                const SkScalar pos[],
-                                               int scalarsPerPosition,
-                                               const SkPoint& offset) {
+                                               SkScalar constY,
+                                               int scalarsPerPosition) {
     SkASSERT(byteLength == 0 || text != NULL);
     SkASSERT(1 == scalarsPerPosition || 2 == scalarsPerPosition);
 
@@ -141,7 +141,8 @@
     // transform is not part of SkPaint::measureText API, and thus we use the
     // same glyphs as what were measured.
 
-    this->init(paint, skPaint, byteLength, kMaxPerformance_RenderMode, offset);
+    const float textTranslateY = (1 == scalarsPerPosition ? constY : 0);
+    this->init(paint, skPaint, byteLength, kMaxPerformance_RenderMode, textTranslateY);
 
     SkDrawCacheProc glyphCacheProc = fSkPaint.getDrawCacheProc();
 
@@ -170,7 +171,7 @@
         }
     } else {
         fTransformType = GrPathRendering::kTranslate_PathTransformType;
-        SkTextMapStateProc tmsProc(SkMatrix::I(), SkPoint::Make(0, 0), scalarsPerPosition);
+        SkTextMapStateProc tmsProc(SkMatrix::I(), 0, scalarsPerPosition);
         SkTextAlignProcScalar alignProc(fSkPaint.getTextAlign());
         while (text < stop) {
             const SkGlyph& glyph = glyphCacheProc(fGlyphCache, &text, 0, 0);
@@ -241,7 +242,7 @@
                                         const SkPaint& skPaint,
                                         size_t textByteLength,
                                         RenderMode renderMode,
-                                        const SkPoint& textTranslate) {
+                                        SkScalar textTranslateY) {
     GrTextContext::init(paint, skPaint);
 
     fContextInitialMatrix = fContext->getMatrix();
@@ -257,7 +258,7 @@
     if (fNeedsDeviceSpaceGlyphs) {
         // SkDraw::ShouldDrawTextAsPaths takes care of perspective transforms.
         SkASSERT(!fContextInitialMatrix.hasPerspective());
-        SkASSERT(textTranslate.isZero()); // TODO: Handle textTranslate in device-space usecase.
+        SkASSERT(0 == textTranslateY); // TODO: Handle textTranslateY in device-space usecase.
 
         fTextRatio = fTextInverseRatio = 1.0f;
 
@@ -339,7 +340,7 @@
         }
 
         SkMatrix textMatrix;
-        textMatrix.setTranslate(textTranslate.x(), textTranslate.y());
+        textMatrix.setTranslate(0, textTranslateY);
         // Glyphs loaded by GPU path rendering have an inverted y-direction.
         textMatrix.preScale(fTextRatio, -fTextRatio);
         fPaint.localCoordChange(textMatrix);