Initial change to move text blob to GrTextContext

src/gpu/GrTextContext.cpp

Index: src/gpu/GrTextContext.cpp
diff --git a/src/gpu/GrTextContext.cpp b/src/gpu/GrTextContext.cpp
index b31c193258534b53e1a1ff1446186d19164db98d..557c2a91976a4d52677866626e971bfd9ab12d3e 100644
--- a/src/gpu/GrTextContext.cpp
+++ b/src/gpu/GrTextContext.cpp
@@ -11,9 +11,11 @@
 #include "GrFontScaler.h"
 
 #include "SkAutoKern.h"
+#include "SkDrawFilter.h"
 #include "SkDrawProcs.h"
 #include "SkGlyphCache.h"
 #include "SkGpuDevice.h"
+#include "SkTextBlob.h"
 #include "SkTextMapStateProc.h"
 #include "SkTextToPathIter.h"
 
@@ -89,6 +91,55 @@ void GrTextContext::drawPosText(GrRenderTarget* rt, const GrClip& clip, const Gr
                             clipBounds);
 }
 
+void GrTextContext::drawTextBlob(GrRenderTarget* rt, const GrClip& clip, const SkPaint& skPaint,
+                                 const SkMatrix& viewMatrix, const SkTextBlob* blob,
+                                 SkScalar x, SkScalar y,
+                                 SkDrawFilter* drawFilter, const SkIRect& clipBounds) {
+    SkPaint runPaint = skPaint;
+
+    SkTextBlob::RunIterator it(blob);
+    for (;!it.done(); it.next()) {
+        size_t textLen = it.glyphCount() * sizeof(uint16_t);
+        const SkPoint& offset = it.offset();
+        // applyFontToPaint() always overwrites the exact same attributes,
+        // so it is safe to not re-seed the paint for this reason.
+        it.applyFontToPaint(&runPaint);
+
+        if (drawFilter && !drawFilter->filter(&runPaint, SkDrawFilter::kText_Type)) {
+            // A false return from filter() means we should abort the current draw.
+            runPaint = skPaint;
+            continue;
+        }
+
+        runPaint.setFlags(fGpuDevice->filterTextFlags(runPaint));
+
+        GrPaint grPaint;
+        SkPaint2GrPaintShader(fContext, fRenderTarget, runPaint, viewMatrix, true, &grPaint);
+
+        switch (it.positioning()) {
+        case SkTextBlob::kDefault_Positioning:
+            this->drawText(rt, clip, grPaint, runPaint, viewMatrix, (const char *)it.glyphs(),
+                           textLen, x + offset.x(), y + offset.y(), clipBounds);
+            break;
+        case SkTextBlob::kHorizontal_Positioning:
+            this->drawPosText(rt, clip, grPaint, runPaint, viewMatrix, (const char*)it.glyphs(),
+                              textLen, it.pos(), 1, SkPoint::Make(x, y + offset.y()), clipBounds);
+            break;
+        case SkTextBlob::kFull_Positioning:
+            this->drawPosText(rt, clip, grPaint, runPaint, viewMatrix, (const char*)it.glyphs(),
+                              textLen, it.pos(), 2, SkPoint::Make(x, y), clipBounds);
+            break;
+        default:
+            SkFAIL("unhandled positioning mode");
+        }
+
+        if (drawFilter) {
+            // A draw filter may change the paint arbitrarily, so we must re-seed in this case.
+            runPaint = skPaint;
+        }
+    }
+}
+
 void GrTextContext::drawTextAsPath(const SkPaint& skPaint, const SkMatrix& viewMatrix,
                                    const char text[], size_t byteLength, SkScalar x, SkScalar y,
                                    const SkIRect& clipBounds) {