Bug 1530322 - P3. Add diagnostics. r=gerald

Depends on D21172

Differential Revision: https://phabricator.services.mozilla.com/D21173

--HG--
extra : moz-landing-system : lando

dom/media/MediaData.cpp

@@ -86,6 +86,8 @@ bool AudioData::SetTrimWindow(const media::TimeInterval& aTrim) {
     // Overflow.
     return false;
   }
+  MOZ_DIAGNOSTIC_ASSERT(trimAfter.value() >= trimBefore.value(),
+                        "Something went wrong with trimming value");
   if (!mTrimWindow && trimBefore == 0 && trimAfter == originalFrames) {
     // Nothing to change, abort early to prevent rounding errors.
     return true;
@@ -93,7 +95,11 @@ bool AudioData::SetTrimWindow(const media::TimeInterval& aTrim) {
 
   mTrimWindow = Some(aTrim);
   mDataOffset = trimBefore.value() * mChannels;
+  MOZ_DIAGNOSTIC_ASSERT(mDataOffset <= mAudioData.Length(),
+                        "Data offset outside original buffer");
   mFrames = (trimAfter - trimBefore).value();
+  MOZ_DIAGNOSTIC_ASSERT(mFrames <= originalFrames,
+                        "More frames than found in container");
   mTime = mOriginalTime + FramesToTimeUnit(trimBefore.value(), mRate);
   mDuration = FramesToTimeUnit(mFrames, mRate);
 

dom/media/MediaData.h

@@ -182,7 +182,7 @@ class AlignedBuffer {
   static size_t AlignmentPaddingSize() { return AlignmentOffset() * 2; }
 
   void PopFront(size_t aSize) {
-    MOZ_ASSERT(mLength >= aSize);
+    MOZ_DIAGNOSTIC_ASSERT(mLength >= aSize, "Popping too many frames");
     PodMove(mData, mData + aSize, mLength - aSize);
     mLength -= aSize;
   }