Switch uses of SkChecksum::Compute to Murmur3.

SkChecksum::Compute is a very, very poorly distributed hash function.
This replaces all remaining uses with Murmur3.

The only interesting stuff is in src/gpu.

BUG=skia:

Review URL: https://codereview.chromium.org/1436973003

2 files changed, 5 insertions, 6 deletions

diff --git a/src/gpu/GrProgramDesc.h b/src/gpu/GrProgramDesc.h
index 05b52cc7cd..9641195354 100644
--- a/src/gpu/GrProgramDesc.h
+++ b/src/gpu/GrProgramDesc.h
@@ -107,8 +107,7 @@ protected:
         *(this->atOffset<uint32_t, GrProgramDesc::kLengthOffset>()) = SkToU32(keyLength);
 
         uint32_t* checksum = this->atOffset<uint32_t, GrProgramDesc::kChecksumOffset>();
-        *checksum = 0;
-        *checksum = SkChecksum::Compute(reinterpret_cast<uint32_t*>(fKey.begin()), keyLength);
+        *checksum = SkChecksum::Murmur3(fKey.begin(), keyLength);
     }
 
     // The key, stored in fKey, is composed of four parts:
diff --git a/src/gpu/GrResourceCache.cpp b/src/gpu/GrResourceCache.cpp
index cb6bcf75fd..4a0c9b2b36 100644
--- a/src/gpu/GrResourceCache.cpp
+++ b/src/gpu/GrResourceCache.cpp
@@ -42,7 +42,7 @@ GrUniqueKey::Domain GrUniqueKey::GenerateDomain() {
 }
 
 uint32_t GrResourceKeyHash(const uint32_t* data, size_t size) {
-    return SkChecksum::Compute(data, size);
+    return SkChecksum::Murmur3(data, size);
 }
 
 //////////////////////////////////////////////////////////////////////////////
@@ -564,7 +564,7 @@ uint32_t GrResourceCache::getNextTimestamp() {
             int currP = 0;
             int currNP = 0;
             while (currP < sortedPurgeableResources.count() &&
-                   currNP < fNonpurgeableResources.count()) {                
+                   currNP < fNonpurgeableResources.count()) {
                 uint32_t tsP = sortedPurgeableResources[currP]->cacheAccess().timestamp();
                 uint32_t tsNP = fNonpurgeableResources[currNP]->cacheAccess().timestamp();
                 SkASSERT(tsP != tsNP);
@@ -596,10 +596,10 @@ uint32_t GrResourceCache::getNextTimestamp() {
 
             // count should be the next timestamp we return.
             SkASSERT(fTimestamp == SkToU32(count));
-            
+
             // The historical timestamps of flushes are now invalid.
             this->resetFlushTimestamps();
-        }        
+        }
     }
     return fTimestamp++;
 }