Makes GrGLProgramDesc's key store the lengths as well as offsets of the effect keys.

src/gpu/gl/GrGLProgramDesc.cpp

Index: src/gpu/gl/GrGLProgramDesc.cpp
diff --git a/src/gpu/gl/GrGLProgramDesc.cpp b/src/gpu/gl/GrGLProgramDesc.cpp
index 2c260cda52b16e3808fc03534b76e6d640ef49fc..27a1fab1e0e1a3e892c1f8866aa38077c64493b7 100644
--- a/src/gpu/gl/GrGLProgramDesc.cpp
+++ b/src/gpu/gl/GrGLProgramDesc.cpp
@@ -14,13 +14,14 @@
 
 #include "SkChecksum.h"
 
-static inline bool get_key_and_update_stats(const GrEffectStage& stage,
-                                            const GrGLCaps& caps,
-                                            bool useExplicitLocalCoords,
-                                            GrEffectKeyBuilder* b, 
-                                            bool* setTrueIfReadsDst,
-                                            bool* setTrueIfReadsPos,
-                                            bool* setTrueIfHasVertexCode) {
+bool GrGLProgramDesc::GetEffectKeyAndUpdateStats(const GrEffectStage& stage,
+                                                 const GrGLCaps& caps,
+                                                 bool useExplicitLocalCoords,
+                                                 GrEffectKeyBuilder* b,
+                                                 uint16_t* effectKeySize,
+                                                 bool* setTrueIfReadsDst,
+                                                 bool* setTrueIfReadsPos,
+                                                 bool* setTrueIfHasVertexCode) {
     const GrBackendEffectFactory& factory = stage.getEffect()->getFactory();
     GrDrawEffect drawEffect(stage, useExplicitLocalCoords);
     if (stage.getEffect()->willReadDstColor()) {
@@ -32,7 +33,17 @@ static inline bool get_key_and_update_stats(const GrEffectStage& stage,
     if (stage.getEffect()->hasVertexCode()) {
         *setTrueIfHasVertexCode = true;
     }
-    return factory.getGLEffectKey(drawEffect, caps, b);
+    factory.getGLEffectKey(drawEffect, caps, b);
+    size_t size = b->size();
+    if (size > SK_MaxU16) {
+        *effectKeySize = 0; // suppresses a warning.
+        return false;
+    }
+    *effectKeySize = SkToU16(size);
+    if (!GrGLProgramEffects::GenEffectMetaKey(drawEffect, caps, b)) {
+        return false;
+    }
+    return true;
 }
 
 bool GrGLProgramDesc::Build(const GrDrawState& drawState,
@@ -105,43 +116,54 @@ bool GrGLProgramDesc::Build(const GrDrawState& drawState,
     if (!skipCoverage) {
         numStages += drawState.numCoverageStages() - firstEffectiveCoverageStage;
     }
-    GR_STATIC_ASSERT(0 == kEffectKeyLengthsOffset % sizeof(uint32_t));
+    GR_STATIC_ASSERT(0 == kEffectKeyOffsetsAndLengthOffset % sizeof(uint32_t));
     // Make room for everything up to and including the array of offsets to effect keys.
     desc->fKey.reset();
-    desc->fKey.push_back_n(kEffectKeyLengthsOffset + sizeof(uint32_t) * numStages);
+    desc->fKey.push_back_n(kEffectKeyOffsetsAndLengthOffset + 2 * sizeof(uint16_t) * numStages);
 
-    size_t offset = desc->fKey.count();
-    int offsetIndex = 0;
+    int offsetAndSizeIndex = 0;
 
     bool effectKeySuccess = true;
     if (!skipColor) {
         for (int s = firstEffectiveColorStage; s < drawState.numColorStages(); ++s) {
-            uint32_t* offsetLocation = reinterpret_cast<uint32_t*>(desc->fKey.begin() +
-                                                                   kEffectKeyLengthsOffset +
-                                                                   offsetIndex * sizeof(uint32_t));
-            *offsetLocation = offset;
-            ++offsetIndex;
+            uint16_t* offsetAndSize =
+                reinterpret_cast<uint16_t*>(desc->fKey.begin() + kEffectKeyOffsetsAndLengthOffset +
+                                            offsetAndSizeIndex * 2 * sizeof(uint16_t));
 
             GrEffectKeyBuilder b(&desc->fKey);
-            effectKeySuccess |= get_key_and_update_stats(drawState.getColorStage(s), gpu->glCaps(),
-                                                         requiresLocalCoordAttrib, &b, &readsDst,
-                                                         &readFragPosition, &hasVertexCode);
-            offset += b.size();
+            uint16_t effectKeySize;
+            uint32_t effectOffset = desc->fKey.count();
+            effectKeySuccess |= GetEffectKeyAndUpdateStats(
+                                    drawState.getColorStage(s), gpu->glCaps(),
+                                    requiresLocalCoordAttrib, &b,
+                                    &effectKeySize, &readsDst,
+                                    &readFragPosition, &hasVertexCode);
+            effectKeySuccess |= (effectOffset <= SK_MaxU16);
+
+            offsetAndSize[0] = SkToU16(effectOffset);
+            offsetAndSize[1] = effectKeySize;
+            ++offsetAndSizeIndex;
         }
     }
     if (!skipCoverage) {
         for (int s = firstEffectiveCoverageStage; s < drawState.numCoverageStages(); ++s) {
-            uint32_t* offsetLocation = reinterpret_cast<uint32_t*>(desc->fKey.begin() +
-                                                                   kEffectKeyLengthsOffset +
-                                                                   offsetIndex * sizeof(uint32_t));
-            *offsetLocation = offset;
-            ++offsetIndex;
+            uint16_t* offsetAndSize =
+                reinterpret_cast<uint16_t*>(desc->fKey.begin() + kEffectKeyOffsetsAndLengthOffset +
+                                            offsetAndSizeIndex * 2 * sizeof(uint16_t));
+
             GrEffectKeyBuilder b(&desc->fKey);
-            effectKeySuccess |= get_key_and_update_stats(drawState.getCoverageStage(s),
-                                                         gpu->glCaps(), requiresLocalCoordAttrib,
-                                                         &b, &readsDst, &readFragPosition,
-                                                         &hasVertexCode);
-            offset += b.size();
+            uint16_t effectKeySize;
+            uint32_t effectOffset = desc->fKey.count();
+            effectKeySuccess |= GetEffectKeyAndUpdateStats(
+                                    drawState.getCoverageStage(s), gpu->glCaps(),
+                                    requiresLocalCoordAttrib, &b,
+                                    &effectKeySize, &readsDst,
+                                    &readFragPosition, &hasVertexCode);
+            effectKeySuccess |= (effectOffset <= SK_MaxU16);
+
+            offsetAndSize[0] = SkToU16(effectOffset);
+            offsetAndSize[1] = effectKeySize;
+            ++offsetAndSizeIndex;
         }
     }
     if (!effectKeySuccess) {