fix color assumption in webm parser

When we get a color tag that doesn't actually
specify the value range, we should not default
to full range values. Instead let's default to
INVALID (which later on defaults to limited range)

Bug: 827893
Change-Id: I137391651fea6b1bff05da20199ebbd8b6cc41e4
Reviewed-on: https://chromium-review.googlesource.com/990778
Commit-Queue: Fredrik Hubinette <hubbe@chromium.org>
Reviewed-by: Dale Curtis <dalecurtis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#548139}

media/formats/webm/webm_colour_parser.cc

@@ -99,6 +99,9 @@ enum class Range : std::uint64_t {
    Defined by MatrixCoefficients/TransferCharacteristics.
    */
   kDerived = 3,
+
+  kMinValue = kUnspecified,
+  kMaxValue = kDerived,
 };
 
 /**
@@ -413,20 +416,23 @@ WebMColorMetadata WebMColourParser::GetWebMColorMetadata() const {
   if (chroma_siting_vert_ != -1)
     color_metadata.ChromaSitingVert = chroma_siting_vert_;
 
-  gfx::ColorSpace::RangeID range_id = gfx::ColorSpace::RangeID::FULL;
-  switch (static_cast<Range>(range_)) {
-    case Range::kUnspecified:
-      range_id = gfx::ColorSpace::RangeID::FULL;
-      break;
-    case Range::kBroadcast:
-      range_id = gfx::ColorSpace::RangeID::LIMITED;
-      break;
-    case Range::kFull:
-      range_id = gfx::ColorSpace::RangeID::FULL;
-      break;
-    case Range::kDerived:
-      range_id = gfx::ColorSpace::RangeID::DERIVED;
-      break;
+  gfx::ColorSpace::RangeID range_id = gfx::ColorSpace::RangeID::INVALID;
+  if (range_ >= static_cast<int64_t>(Range::kMinValue) &&
+      range_ <= static_cast<int64_t>(Range::kMaxValue)) {
+    switch (static_cast<Range>(range_)) {
+      case Range::kUnspecified:
+        range_id = gfx::ColorSpace::RangeID::INVALID;
+        break;
+      case Range::kBroadcast:
+        range_id = gfx::ColorSpace::RangeID::LIMITED;
+        break;
+      case Range::kFull:
+        range_id = gfx::ColorSpace::RangeID::FULL;
+        break;
+      case Range::kDerived:
+        range_id = gfx::ColorSpace::RangeID::DERIVED;
+        break;
+    }
   }
   color_metadata.color_space = VideoColorSpace(
       primaries_, transfer_characteristics_, matrix_coefficients_, range_id);