Start to rework DM JSON handling.

dm/DMExpectations.h

 #ifndef DMExpectations_DEFINED
 #define DMExpectations_DEFINED
 
 #include "DMTask.h"
-#include "gm_expectations.h"
 
 namespace DM {
 
 struct Expectations {
     virtual ~Expectations() {}
 
     // Return true if bitmap is the correct output for task, else false.
-    virtual bool check(const Task& task, SkBitmap bitmap) const = 0;
-};
-
-class NoExpectations : public Expectations {
-public:
-    NoExpectations() {}
-    bool check(const Task&, SkBitmap) const SK_OVERRIDE { return true; }
-};
-
-class JsonExpectations : public Expectations {
-public:
-    explicit JsonExpectations(const char* path) : fGMExpectations(path) {}
-
-    bool check(const Task& task, SkBitmap bitmap) const SK_OVERRIDE {
-        SkString filename = task.name();
-        filename.append(".png");
-        const skiagm::Expectations expectations = fGMExpectations.get(filename.c_str());
-
-        if (expectations.ignoreFailure() || expectations.empty()) {
-            return true;
-        }
-
-        // Delay this calculation as long as possible.  It's expensive.
-        const skiagm::GmResultDigest digest(bitmap);
-        return expectations.match(digest);
+    virtual bool check(const Task& task, SkBitmap bitmap) const {
+        return true;
     }
-
-private:
-    skiagm::JsonExpectationsSource fGMExpectations;
 };
 
 }  // namespace DM
 
 #endif // DMExpectations_DEFINED